Proposed commit log message:
```
Mk/bsd.options.desc.mk: Add version control OPTIONS descriptions
- Add BAZAAR description
- Add CVS description
- Add DARCS description
- Add GIT description
- Add MERCURIAL description
- Add PERFORCE description
- Add RSYNC description
- Rename SVN to SUBVERSION
Reviewed_by: koobs
Approved by: koobs (mentor)
Differential_Revision: D17459
```