Updated date to 2013 in copyright headers
Use '_' for variables that are unused

To suppress errors with haxe3 pattern matching
Force properties to use (get,set) for Haxe 3

(You can no longer use a custom method name)
Slight interface changes for implements/extends in haxe 3
Change Stack to CallStack (haxe3 change)
Change Hash<T> to Map<String,T> (haxe3)
Update LICENSE file to 2013