MBF for deprecating Python2 usage

[Matthias Klose <doko@debian.org>]

While at DebCamp, Stefano Rivera and I sat down to analyze what needs to be done
to deprecate Python2 usage within the distribution.  It might not be possible to
drop Python2 for the next release, but there are still too many issues with
packages.  For now we identified some categories which need fixing. These are
documented at https://wiki.debian.org/Sprints/2017/Python3Montreal, resulting in
more than 3000 bug reports.  That's a high number, on the other hand we won't
make much progress if the issues are not named.  My intent is to bring that up
in the Python BoF next week at DebConf and then filing these bug reports with
the user tags mentiond on the wiki page.

Matthias