Tools for Debian Release Team work

 drt-tools includes tools to help with typical work of Debian's release
 team. Currently, it processes excuses.yaml to check for packages that
 require a binNMU for migration to testing, prepares a list of binNMUs
 for transitions, and so on. It provides the following sub-commands:
 .
  * grep-excuses: Mostly the same as the tool of the same name from
    devscripts.
  * process-excuses: Download and process excuses.yaml to generate a list
    binNMUs for packages that require them for migration. Packages that
    have other issues preventing them from migrating, are not considered.
  * process-unblocks: Download and process excuses.yaml to generate a
    list of unblocks for packages in tpu and some other cases.
  * nmu-transition: Take a list packages copies from ben's output and
    schedules binNMUs.
  * nmu-eso: Produce and schedule a list of rebuilds for packages having
    Built-Using on source packages with Extra-Source-Only: yes set.