Merge branch 'dev' of https://github.com/GoodBoyDigital/pixi.js into dev

Tweaked interaction manager to handle mouse leave events better

TilingSprite fixes for CocoonJS, closes #490

Merge pull request #492 from drkibitz/ducktype ...

Duck type img

Merge pull request #537 from cacheflowe/dev ...

Protect against NaN rotation values

Reusing children and use pool object. ...

When need update BitmapText very often it is not the best way  to create new Sprites and remove old.
So better way is reusing it and use pool object.

Remove all references to mat3 or mat4

Protect against NaN rotation values ...

Throws an Error if a DisplayObject's rotation was set to NaN. Without this check, Sprite's textures could disappear silently, with no reference to the improper rotation value as the culprit.

fix typo in graphics webgl render

Fixed type in bitmap font

Tweaked tiling texture and jshinted code

Tweaked getLocalPosition ...

Also cahced css cursor reference in js

fixed render texture issue and jshinted code

replaced matrix

Merge branch 'dev' of https://github.com/GoodBoyDigital/pixi.js into dev

Reset Alpha for CanvasRenderer

A nice getter/setter for our lovely users

Dived into WebGLRenderer, fixes and docs

return empty rect if container has no visible children

Allow texture to not be flipped

jslinted code

Docs updated ...

Fixed issue where alpha not being set correctly in canvas spriteBatch
Fixed issue where previous stage events did not get removed correctly

Typos and Started tackling the WebGL, and tests

Docs :)

Fixed, finally adapted to the dev branch

Manually merge #522 from @qzix13

Added auto prevent default variable to pixi constants

Mad cross origin on by default to fix ie11 issue and make life generally easier

Added constant for interaction frequency

Fixed premultiplied alpha - for webGL transparent canvas