Merge pull request #243 from jcd-as/dev

move 'dirty' flag for Tilemap to a per-layer flag. Fixes #242
* When a Sprite is destroyed any active filters are removed as well.
* Updated Pixi.js so that removing filters now works correctly without breaking the display list.
Introduced a separate stage.fullScreenScaleMode property that is used to decide scaling when fullscreen.
Switch Camera.setBoundsToWorld to match world.bounds instead of world
Added a fix for fullscreen scaling in firefox.
Merge pull request #245 from oysterCrusher/dev

Introduced a separate stage.fullScreenScaleMode property.
Merge pull request #250 from cocoademon/camera_bounds_fix

Switch Camera.setBoundsToWorld to match world.bounds instead of world
Group.length now returns the number of children in the Group regardless of their exists/alive state, or 0 if the Group is has no children.
Lots of new tilemap code in here. If your game relies on tilemaps then please don't update to this commit unless you want to help debugging!
Fixed an issue where passing null as the Group parent wouldn't set it to game.world as it should have (thanks tito100).
Continued work on the tilemap collision - again, please don't use this version if you need working tilemaps.
Mostly working, just need to apply a max overlap to avoid tunneling, although a ray would be better.
Added max overlap clamp.
Tilemap collision fixed, regardless of rotation, number of overlapping tiles and speed (to a point anyway). Maps also don't crash if they are smaller than the render area. Layers can be positioned successfully anywhere in camera but collision isn't yet offset for this.
TypeScript file updated, now compiles without error in VS and FlashDevelop.
Added Tutorial 2.