[kivihiinlane]

This is exactly what I was looking for few months back.

I was working on a rather large and very messy project back then. Project used popular framework with very specific config files but previous dev choose to ignore them most of the time so configurations were all over the place. I didn't have much time to start looking more deeply into the git so I just ended up using 'local-config' branch that had my environment specific configs that I always rebased on top of master and deleted on commit. Wasn't perfect solution but it worked.