- using a single JS source for all examples instead of duplicating files unnecessarily.
- updating Gruntfile and package.json to include grunt-concat-sourcemap and grunt-contrib-watch for easier development.
- use "grunt build-debug" to build a source-mapped file to pixi.dev.js -- or use "grunt watch" during development of examples to auto build-debug any JS changes to PIXI source or the example files.
Merge pull request #374 from mattdesl/concat-sourcemaps

Changes to Development Workflow
New Filter Structure

Base Filters now working for graphics and sprite
Filters now nestable
Merge branch 'dev' of https://github.com/GoodBoyDigital/pixi.js into dev
Filters updates

Added new filters
Added ability for filters to have multiple passes
Optimized texture creation for filters
Example updated and redundant files deleted
Tweaks to Filters runing in render Texture

Added Blur Example
Filter Tweaks

Displacement Map Filter tweaked
Demos created
Docs updated
All Filter Exampls Added

Example 16 removed as no longer required
added Color step filter
added Twist filter
added Dot screen
WebGL masking issue fixed

WebGL mask objects can now be nested within masked objects
Line width now more accurate
Removed rogue console.log
Graphics Bug fixs

Fixed bug where webGL graphics not working in safari
Fixed bug where Collinear points cause lines to be draw oddly
Moved program uniforms

Moved program uniforms locations to the PixiShader rather than the
glProgram
Fixed Issue #313
Merged with upstream changes. Also fixed the default width/height implementation.