CCTileMapInfo: Notify users of unsupported tile-map encoding file types
CCTileMapInfo: Notify users of unsupported tile-map encoding file types

* In relation to issue #141
* Previous debug assert methods have been replaced with Unsupported exceptions so that release builds will be notified

haithemaraissia/CocosSharp,MSylvia/CocosSharp,TukekeSoft/CocosSharp,haithemaraissia/CocosSharp,mono/CocosSharp,mono/CocosSharp,MSylvia/CocosSharp,zmaruo/CocosSharp,zmaruo/CocosSharp,TukekeSoft/CocosSharp