Replace typedef enums with typedef NS_ENUM.
For one thing, it make Swift happier. Also, we don’t have to worry about what size/type the value is.
Change ints in NS_ENUMs to NSIntegers.
Change SUCharacterType to an NSInteger.
Merge pull request #398 from MaddTheSane/nsEnumedEnums

Change enums to NS_ENUMs
Warn when version is missing
Code formatting