AntTaskManager refactor

- don't use Reflection + Dynamics for the callbacks anymore, but properly typed functions of type Bool->Void. This allowed the removal of Object. Also removed Args, bind() can be used for that on the function.
- now extends FlxBasic instead of FlxPlugin - plugins are designed to only ever have one instance
- don't iterate of the whole linked list for getting the length, increment and decrement it instead if tasks are added and removed
- removed pause / _isPaused, active should be used for that