Fixed TilingSprite not render children on canvas

TilingSprite does not render children on 2d canvas. The call to
children's renderCanvas method is missing.
Fix Text.destroy() and fix memory leak in BaseTexture.destroy() if basetexture was from canvas
Implemented animationSpeed for Spine animations.
Default value is 1.
This is simply the "timeScale" value from the Spine runtime, but with a more friendly name.
initial implementation of new bubbling event target
Convert the library to use new event methods
fix some event changes that were overzealous
move listeners to be lazy added
change to a prototype/mixin model
Fixed a minor typo in Sprite constructor documentation

Changed `nex` to `new` and `Sprite.FromImage` to `Sprite.fromImage`
Strip and Rope now working again

added rope example
minor tweaks
Merge pull request #722 from n1313/patch-2

Fixed a minor typo in Sprite constructor documentation
Fixed Graphics blendMode

Graphics blendMode property now works in webGL
Merge branch 'dev' of https://github.com/GoodBoyDigital/pixi.js into dev
Fixed Tiling Sprite bug
premultipliedAlpha for webgl textures
added width and height properties to displayObject

Also anded render back into text example
Merge pull request #647 from giraluna/destroy

Fix Text.destroy() and memory leak in BaseTexture.destroy()
Merge pull request #659 from ryanmcnz/dev

Implemented animationSpeed for Spine animations.
Option to set premultipliedAlpha on webgl context
If the texture is destroyed, it should be removed from TextureCache too