broken support for local repo bases

[nmeyerhans]

Somewhere along the lines, support for repo bases (-b) on local filesystems got dropped. When using git-multipkg from commit 6ccefbf, the following succeeds:
git-multipkg -b /home/noahm/src multipkg

But with more recent revisions(e.g. b94a318), it fails with
"unsupported base at /usr/bin/git-multipkg line 176."

[nmeyerhans]

It also looks like support for read-only git protocol repo bases e.g. git://github.com/ytoolshed) is broken.

[cuzelac]

Thanks Noah. In truth, we need a real test suite for all these ytoolshed tools.

I'm poking around with this on branch ISSUE-12