Add option to search projects parent folders to get the current git branch

[eh-iart]

• Add option to search parent folders reclusively for current git branch
  This can be useful when the Unity project is not in the root of the git repository but you still like to see it in the launcher.

Note:
I had to add a new setting useAlphaReleaseNotes to the Settings, i'm not sure what happend there, but i was not able to build without it...

[unitycoder]

thanks, i'll have a look!

[unitycoder]

ok looks good, i'll adjust the settings row length later though (as the StackPanel pushes other settings out from window right border, if its narrow like mine)