rename message handler files
mixin base `handleMessage` into `handleMessagePath/Group`
minor cleanup
add `handleMessage#createRenderObject()` and `handleMessageStage`
Rename `update` to `updateAttributes`
add “Group” (nested DisplayObjects) support
refactor `_applyGeometry` and add `messageHandler#updateGeometry`
add line-breaks
rename `handleMessage#remove` to `detach` and fix action
Add “transformMatrix” API to pixi.js
turn on antialias
add Bitmap support
add incomplete Filter support
warning: Text is not supported yet