Split MGLDirectionFormatter into MGLClockDirectionFormatter, which specializes in clock positions, and MGLCompassDirectionFormatter, which boxes the compass. This neatly avoids any confusion that might arise if the developer fails to read the documentation and thinks the original unified formatter can convert between the two types of directions.
Implemented an NSFormatter for formatting CLLocationDirection values as localizable display strings. The formatter supports both absolute compass directions, such as “south”, and relative “clock” directions, such as “6 o’clock”.
Added a degree-minute-second coordinate formatter for general use. Use this formatter in iosapp and osxapp.
Added unit tests for the coordinate formatter and for round-tripping geometry types through NSValue.
Renamed SDK classes related to offline viewing to more closely match the terminology used by mbgl and the Android SDK while remaining consistent with Cocoa naming principles.
