cleanup merge-base test script
cleanup merge-base test script

Add a picture, and keep the setup and the tests together.

Signed-off-by: Sam Vilain <9e3d9c151a1935fa51df4c7420358e0667b0b28d@catalyst.net.nz>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git