[Feature] more (D)VCS abstract.

[ghost]

Hello! Just a little thought that I had.

I was looking at sam and thought that it is strange that it only supports git...
It would have been better if it was possible to use different (D)VCSs like SVN, Bazaar or Mercurial.

I know this would require a little tinkering with the classes to begin with (make an abstract Repo class and extend from that (GitRepo, BzrRepo, SvnRepo, HgRepo)) and make a URL resolver (If it is a Launchpad's bzr URL it starts with "lp:" for example, whilst their git URLs do not).

There are a few problems with this: one in that it can be hard to resolve what type of repository one is dealing with. The other problem is that the UI (command line) needs to have a little change of language (clone to something else to be more generic -- git clone, hg clone, bzr branch, svn checkout, etc -- are the same basically).

The first problem could be solved by changing the YAML format a little (adding a Type field), but that could break stuff.

Just a thought. :-)