Remove the coverage numbers from the README
support custom refs in Repository.contents()
Merge branch 'develop'
Release 0.5.3

Thanks @tpetr for the fix
Add gbp.conf
Merge branch 'master' into debian
New debian package
Ignore more non-shipped files

The package is now built from the tarball generated by setup.py sdist
instead of git-archive, so we need to ignore all files not shipped by
sdist.