GenerateBuildNumber script: fixed for git
GenerateBuildNumber script: fixed for git

Apparently never added support for Git to this script. Done
now, anyway.

Signed-off-by: Steven Noonan <4068f0880b399410602d694b3cc711c8a8f4727e@uplinklabs.net>

tycho/crisscross,prophile/crisscross,tycho/crisscross,prophile/crisscross,tycho/crisscross,prophile/crisscross