- test_repository() uses `git init-db` for init under older git
versions (although the test suite hasn't yet been adapted to
support really old versions of git)
- fixed a typo in the error message for test_repository()
- made some tests for failure a little more lax when looking for
the "fatal:" string in the errput (i.e. look for it at the beginning
of any line, not just the firts)
- various minor documentation improvements
- the "OTHER GIT WRAPPERS" is really a "SEE ALSO" section