FileStore 13.01

Big steps this month in finializing the V1 protocol, starting with a more formal specification:

  http://docs.novacut.com/filestore/specification.html

Still to be decided is whether we'll switch to a custom base-32 encoding to fix the sort-order problem with RFC-3548 Base32 encoding, detailed here:

  http://docs.novacut.com/dbase32/design.html

Code changes include:

  * Reworked filestore into a Python package (rather than a single Python module)

  * Added new filestore/protocols.py module that cleanly separates the functionality that any protocol will have in common from the details that will be unique to a protocol version. This makes R&D on future protocols easier, also helps us move more quickly on finalizing the V1 protocol.

  * Started work on making all code-paths select protocol version by ID length. This forces us start building things in a future-proof way now, and helps verify that selecting based on ID length is a workable design.

  * Added new filestore/misc.py module, to which TempFileStore has been relocated (this avoids a few imports in `filestore`, lowers our idle memory footprint)

  * Added experimental fast_b32encode() C extension