Merge pull request #484 from Gama11/dev_imports

Fix all imports, each class has its own file now, misc issues
Merge pull request #485 from Gama11/dev_cleanup

Cleanup for flixel.addons
SfxFader fix (the issue has been caused by change of CompleteCallback type)
fix for previous SfxFader's fix :)
Merge pull request #486 from Gama11/dev_cleanup

Cleanup for flixel.effects
little FlxPreloader "improvement"