o Added the properties opaque and cacheable to tile sources
o Unique tile cache key for every grid setting in RMCoordinateGridSource
o Added -removeAllCachedImagesForCacheKey: to the tile caches
o Added RMCompositeSource for efficiently compositing opaque and non-opaque tile sources
fixes #104: MapBox improvements
o Check for some error conditions
Merge pull request #105 from mapbox/104-mapbox-improvements

fixes #104: MapBox improvements
o Some merge fixes for pull request #105
o Sample projects updates due to pull request #105
o Some merge fixes
Merge branch 'release' into develop
o Slightly darker default label color for the coordinate grid
o Added tileSourceHasTile: to the tile sources
Merge branch 'release' into develop
README cleanups
bring over tracking mode fix from mapbox/mapbox-ios-sdk#118
tracking button XIB enhancement from mapbox/mapbox-ios-sdk#106
annotation.enable enhancement from mapbox/mapbox-ios-sdk#141
minor nitpicks with doc text & getter syntax for tile protocol
Merge pull request #113 from mapbox/tile-source-nitpicks

minor nitpicks with doc text & getter syntax for tile protocol