First step in two-part process to rename directories to kallithea.
This first step is to change all references in the files where they refer
to the old directory name.

synced vcs with upstream

- moved subprocessio module to VCS
- many small changes to make embedded vcs as similar to to external lib
- use only absolute imports
- patch vcs config during load pylons env

commit less models
- models don't do any commits(with few exceptions)
- all db transactions should be handled by higher level modules like controllers, celery tasks