Diff of NSMutableArray

• The added line is THIS COLOR.
• The deleted line is THIS COLOR.
• Go to NSMutableArray.

- [[NSObject]]

- [[NSArray]]

-NSArrayとNSMutableArrayの相互変換
--   http://qiita.com/mikansensei/items/34eecfcdb08cc1e8e7db
-  Merging NSArrays in Objective-C
--  http://stackoverflow.com/questions/1279586/merging-nsarrays-in-objective-c
 [NSMutableArray addObjectsFromArray:]