This way, we don't rely on automatic scheme creation in Travis, nor do we have to update the Makefile for Travis if we want to add an additional test target to the project. Also, Travis should now build all targets (including BinaryDelta and Sparkle Test App), giving us better build coverage.
CFBundleShortVersionString is now used to embed the Git rev info instead.
This helps ensure that all code paths are compiled during development, reducing the chance of build errors (especially in CI). Additionally, developers can change these values without having to rebuild Sparkle (but it is still safe because modifying the plist will break the code-signing seal).