SRU of LXD 2.0.10 (upstream bugfix release)

LXD upstream released LXD 2.0.10 as a bugfix release with following changelog:
    - client: Backported the new client library and ported some of the
      internal commands over to it
    - lxc: Add a manpage command
    - lxc: Allow --version to be passed with any command
    - lxc: Reworked all help messages in the client to work with help2man
    - lxd: AppArmor namespacing is now also enabled for privileged containers

    - build: Add debug logging
    - client: Fix profile list
    - client: Remove unneeded condition
    - doc: Add instructions to grow ZFS loop
    - doc: Add note about escaping btrfs qgroups
    - doc: Add note about restricting access to kernel ring buffer
    - doc: Extract containers documentation to containers.md
    - doc: Extract profiles documentation to profiles.md
    - doc: Extract server documentation to server.md
    - doc: Fix badly named example device
    - doc: Fix broken table
    - doc: Note that LXD assumes full control over the pool
    - doc: Update configuration.md with links to other documents
    - doc: Update README.md for new API client
    - extra/lxc-to-lxd: Don't crash on missing mount file
    - extra/lxc-to-lxd: Typo in description of --move-rootfs
    - extra/vagrant: Trailing whitespace
    - global: Fix error handling in all filepath.Walk calls
    - global: Fix a number of typos
    - global: Forward user-agent and other headers on redirect
    - global: Replace file Chmod() with os.Chmod()
    - global: Use containerGetParentAndSnapshotName()
    - global: Use RunCommand everywhere
    - lxc: Don't include spaces in translated strings
    - lxc: Improve batch mode
    - lxc: Make help/usage a bit more consistent
    - lxc: Move common functions/types to utils.go
    - lxc: Properly clear transfer stats on error
    - lxc: Rework for better manpages
    - lxc/config: Add new config handling code
    - lxc/config: Always use "simplestreams" for images:
    - lxc/config: Fix path handling
    - lxc/config: Fix SaveConfig's DeepCopy call
    - lxc/copy: Improve error handling
    - lxc/copy: Return the source error too
    - lxc/copy: Simplify
    - lxc/copy: Wait asynchronously
    - lxc/image: Show the alias description
    - lxc/image: Trailing whitespace
    - lxc/init: Drop unnecessary else statement
    - lxc/list: Document list format options
    - lxc/list: Fix regression in json output
    - lxc/list: Move common data extraction to a helper function
    - lxc/profile: Properly implement "profile unset"
    - lxc/publish: Wait for the conainer to be running
    - lxc/remote: Show the fingerprint as string not hex
    - lxc/utils: Implement progress tracking for operations
    - lxd: Drop use of logger.Log when not needed
    - lxd/apparmor: Fix AppArmor stack handling with nesting
    - lxd/containers: Add containerGetParentAndSnapshotName()
    - lxd/containers: Added soft limit in initLXD()
    - lxd/containers: Added soft memory limit even when hard is selected
    - lxd/containers: Add extra validation for unix-block/unix-char
    - lxd/containers: Add function to detect root disk device
    - lxd/containers: Allow for stable host interface names
    - lxd/containers: Clarify uid/gid error
    - lxd/containers: Cleanup root device validation
    - lxd/containers: Disable IPv6 on host side veth when bridged
    - lxd/containers: Don't ignore snapshot deletion failures
    - lxd/containers: Don't parse id ranges as int32
    - lxd/containers: Don't report migration success on failure
    - lxd/containers: Don't use FindProcess, just pass exec.Cmd
    - lxd/containers: Find current max snapshot value
    - lxd/containers: Fix bad root device detection code
    - lxd/containers: Fix base image tracking
    - lxd/containers: Fix concurent read/write to s.conns in exec
    - lxd/containers: Fix error handling on FileRemove
    - lxd/containers: Fix handling of devices with minor>255
    - lxd/containers: Fix override of Devices during copy
    - lxd/containers: Fix soft limit logic to use float64
    - lxd/containers: Initialize idmap on demand
    - lxd/containers: Kill forkexec on abnormal websocket closure
    - lxd/containers: Path may only be used by one disk
    - lxd/containers: Properly invalidate the idmap cache
    - lxd/containers: Properly revert memory limits on failure
    - lxd/containers: Properly validate architectures
    - lxd/containers: Set default values for USER, HOME and LANG
    - lxd/containers: This condition has already been deal
    - lxd/containers: Use int64 for uid and gid everywhere
    - lxd/containers: Validate container idmap as early as possible
    - lxd/containers: Validate expanded configuration after root setup
    - lxd/containers: Validate the expanded config at container create
    - lxd/daemon: Check for the validity of the id maps at startup
    - lxd/daemon: Fix some race conditions
    - lxd/daemon: Mount a tmpfs under devlxd
    - lxd/daemon: s/Default map/Available map/
    - lxd/daemon: Set ServerFingerprint
    - lxd/daemon: Use a tmpfs for shmounts
    - lxd/db: Actually enable foreign keys per connection
    - lxd/db: Deal with the case where no updates exist
    - lxd/db: Detect downgrades with newer DB and fail
    - lxd/db: Raise DB lock timeout to 30s, retry every 30ms
    - lxd/db: Rely on CASCADE
    - lxd/db: Remove some extra cleanup code
    - lxd/devlxd: Fix extraction of fd from UnixConn with go tip
    - lxd/events: Improve formatting in events API
    - lxd/images: Check if the image already exists
    - lxd/images: Drop leftover debug statement
    - lxd/images: Fix partial image fingerprint matches
    - lxd/images: Move imagesDownloading out of the daemon struct
    - lxd/images: Properly return the alias description
    - lxd/images: Record the server certificate in the cache
    - lxd/images: Refactor code a bit
    - lxd/images: Save image source certificate and pass it to the download
    - lxd/images: Split autoUpdateImage function
    - lxd/init: Only show userns message if lacking uid/gid
    - lxd/init: The 'storageBackend' has already been checked
    - lxd/main: Fix comment in activateifneeded
    - lxd/main_forkexec: Remove os.FindProcess
    - lxd/main_netcat: Implement logging
    - lxd/main_netcat: Switch to new helper
    - lxd/main_nsexec: cgo: Free allocated memory
    - lxd/main: Restrict daemon and activateifneeded to root
    - lxd/migration: Better handle rsync errors (subprocesses)
    - lxd/migration: Clarify CRIU related errors
    - lxd/migration: Handle EAGAIN properly
    - lxd/migration: Make our netcat handle EAGAIN
    - lxd/migration: Tweak rsync logging a bit
    - lxd/operations: Remove useless for loops
    - lxd/profiles: Verify root disk devices
    - lxd/storage/btrfs: Always use the recursive subvol functions
    - lxd/storage/btrfs: Cleanup empty migration dirs
    - lxd/storage/btrfs: Fix recursive subvol deletion
    - lxd/storage/btrfs: Properly handle nested subvolumes
    - lxd/storage: Ensure the container directory has the right permission
    - lxd/storage: Move mount helpers to storage utils
    - lxd/storage: Optimize containerGetRootDiskDevice a bit
    - Makefile: Always include gorilla/context
    - Makefile: Drop repeated calls to "go get"
    - Makefile: Use system libsqlite3 if available
    - shared: coding-style pedantry
    - shared/api: Add the Stateful field to ContainerPut
    - shared/api: Properly define the image creation source
    - shared/api: Use consistent json and yaml field names
    - shared/cmd: Add a new shared/cmd package with initial command I/O logic
    - shared/cmd: Complete cmd.Context support for various AskXXX methods
    - shared/gnuflag: Fix golint
    - shared/i18n: Simplify and make golint clean
    - shared/idmap: DefaultIdmapSet is always for root
    - shared/idmap: Drop GetOwner
    - shared/idmap: Fix various issues
    - shared/idmap: Implement parsing of kernel id maps
    - shared/idmap: Implement Usable() functions
    - shared/idmap: Improve parsing of the shadow id files
    - shared/idmap: Make more of an effort to find a default
    - shared/idmap: Remove debugging during idmap changes
    - shared/ioprogress: Simplify and make golint clean
    - shared/logger: Add pretty formatting
    - shared/logger: Create new package for logger
    - shared/logger: Make golint clean
    - shared/logger: Replace PrintStack with GetStack
    - shared/logging: Export LogfmtFormat
    - shared/logging: Make golint clean
    - shared/simplestreams: Always prefer squashfs when available
    - shared/simplestreams: Export image file list
    - shared/simplestreams: Improve error handling
    - shared/simplestreams: Properly handle image rebuilds
    - shared/termios: Make golint clean
    - shared/util: Add function to detect errno
    - shared/util: Add yaml-mode marker in template for "lxc edit" actions.
    - shared/util: Don't do chown on windows
    - shared/util: FileCopy should also keep owner
    - shared/util: FileCopy should keep the same mode
    - shared/version: Make golint clean
    - tests: Add a testify test suite for db tests, rework existing tests
    - tests: Add golint
    - tests: Add lxd init --auto tests
    - tests: Allow random storage backend selection
    - tests: Also unmount the devlxd path
    - tests: Always cleanup loop devices
    - tests: Avoid a zfs race
    - tests: Don't leak zpools in "lxd init" test
    - tests: Explicitly pass shell type to shellcheck
    - tests: Fix lxd auto init test suite
    - tests: Fix typo
    - tests: Give more time to reboot test
    - tests: Honor the LXD_BACKEND environment variable in storage tests
    - tests: Improve performance of deadcode test
    - tests: Make sure a client certificate is generated
    - tests: Make sure storage volume is mounted
    - tests: Properly cleanup in template testsuite
    - tests: Record how long the tests take
    - tests: Remove invalid test for Jenkins
    - tests: Run golint on client/ and lxc/config/
    - tests: Switch to use gofmt instead of "go fmt"
    - tests: Testsuites are sourced, not executed
    - tests: The monitor can exit on its own
    - tests: Trailing whitespaces
    - tests: Update for new client
    - tests: Update init test for stable branch
    - tests: Use flake8 instead of separate pyflakes and pep8
    - tests/deps: Make golint clean
    - tests/lxd-benchmark: Fix --help and --version handling

Just like Ubuntu itself, upstream releases long term support releases, as is 2.0 and then periodic point releases including all the accumulated bugfixes.

Only the latest upstream release gets full support from the upstream developers, everyone else is expected to first update to it before receiving any kind of support.

This should qualify under the minor upstream bugfix release allowance of the SRU policy, letting us SRU this without paperwork for every single change included in this upstream release.

Once the SRU hits -updates, we will be backporting this to trusty-backports as well, making sure we have the same version everywhere.