Small fix for very specific bug in Delay component
Merge pull request #762 from heniotierra/delay_bug_fix

fix to issue #761
Decouple Crafty.pixelart from individual renderers

Currently `Crafty.pixelart()` explicitly alters the canvas and DOM renderers.  This PR has it fire an event instead.

The canvas and DOM contexts now listen for the event, and make the appropriate changes.  This will make it simpler to add new contexts (like webgl) or to introduce multiple renderers of the same type.

This patch also tracks the current pixelart setting, and ensures that, when a canvas context is inited, that it matches that value.  It doesn't do something similar for the DOM element because the stage is created as soon as you init Crafty.
Merge pull request #765 from starwed/eventify-pixelart

Decouple Crafty.pixelart from individual renderers
Improve COllision docs

Adds practical examples to the collision features introduced in #699 .
All tests invoked from a single file.
Playgrounds are now in their own independent directory.
Merge pull request #763 from grozen/separate-playgrounds

All tests invoked from a single file
Move color and tint into new file
Refactor Color and remove Tint

This patch
- eliminates Tint and adds its capabilities to Color.  (Works with DOM now, since we don't need to worry about IE8 etc.)
- adds a new method (Crafty.assignColor) for converting any string representation of a color into rgb(a) components
- removes `Crafty.toRGB` in favor of this new method.
Merge pull request #770 from starwed/color-tint-refactor

Color, Tint refactoring
Fix for propogating 90deg rotations to child entities
Merge pull request #774 from FallSe7en/develop

Fix for propogating 90deg rotations to child entities
Merge pull request #768 from mucaho/collision_docs

Improve Collision docs
Add additional game loop events

Fixes #478 .
Add audio_isPlaying.
Refactor "Delay" to use dt from frameData

Rather than explicitly requesting the current time, the "Delay" component should just accumulate the time passed in by the "EnterFrame" event.  This way it doesn't need to worry about tracking the pause state of the game; that's all handled by the main game loop.

This meant drastically simplifying the tests -- they no longer need to overwrite the Date object or anything like that.
Merge pull request #775 from starwed/simpler-delay

Refactor "Delay" to use dt from frameData
Refactored loader; created function 'removeAssets'; fixed bug in Crafty.audio.remove
Merge pull request #778 from mucaho/audio_isPlaying

Add audio_isPlaying.
Merge pull request #769 from mucaho/more_events

Add additional game loop events