Move and rename the existing git-interface tests such that tests for
other scripts can be added easily.
In particular, the following changes are made:
* Move the existing tests from git-interface/test/ to test/.
* Rename t0001-auth.sh to t1100-git-auth.sh.
* Rename t0002-serve.sh to t1200-git-serve.sh.
* Rename t0003-update.sh to t1300-git-update.sh.
Signed-off-by: Lukas Fleischer <lfleischer@archlinux.org>
