rename some methods so Bitflags works on subclasses of Entity
Entity
move tick() and draw() to MainLoop, doTick->tick, doDraw->draw
doChildren->processChildren
add as() method
revert: remove Mathematics.int() for cpp as leads to some problems with the generated code
haxe3 fixes (breaks haxe2)
Merge branch 'dev' of github.com:polygonal/core into dev