convert to ARCLite (required OSX 10.6 and Xcode 4.2 or above, 64bit only)
clean up deprecatd API (replace filename method of NSSavePanel)
Static Analyzerの分析に従ってsingletonの実装を変更
Inline function replace macro returned object because code completion is worked well
Added managed object subclass to property belonging to data model
clean up deprecated API (beginSheetForDirectory... method of NSSavePanel class replace)