When egnerating the iOS metabase, don't inject the class as returnType for methods with "instancetype" returnSubtype. Allow that resolution to be dynmaically on lookup. Otherwise we'll mess up resolutions for something like NSMutableArray.array(). It will think the returntype is "NSArray" when it's actually NSMutableArray.
Merge pull request #53 from sgtcoolguy/delay_instancetype

delay_instancetype