More work on versioning

The new versioning scheme looks like these: vMajor.Minor.BuildNumber BuildType

Major and Minor are in the source code. Currently set to 2.1 as a starting point past the existing 2.0.3 old number. BuildNumber and BuildType are meant to come from command line. If no BuildNumber on command line it defaults to 0. If no BuildType on command line it defaults to "(Developer Build)".

TeamCity will do the following (doesn't yet, will work on it after this goes through):
-Set BuildNumber to an incrementing build number
-Set BuildType to "(Daily Build)" for dailies
-Set QGC_APPLICATION_VERSION_COMMIT to the sha1 for the commit this is built from. This will be used in an upcoming About box.

When we set aside stable builds, the Minor version will be bumped and the BuildType will be set to "(Stable)".

Other stuff:
- I removed the broken settings reset api. There is in Issue on this. I'll update that to include putting it back in a working state.
- This change requires a settings version bump since I found other problems with the way settings were used. See commits comments for details on those changes changes.