Initial integration of Debian package work.

 I've taken SourceRpm (almost entirely) and changed it's name to be a
 "DebianSource" package.

 The only major change is that DebianSource packages have no arch, we'll
 leave that for the DebianBinary bits.
Adding some light documentation to DebianSource

 Just braindead docstrings; nothing people shouldn't be able to guess.
raindead error; forgot to remove build arch
Compacting the source line to a single one.
Merge pull request #6 from paultag/feature/debian-integration

Feature/debian integration