Merge pull request #6 from HaxeFlixel/dev

Dev
Update FlxG.hx
Renaming FlxCollisionType.NULL to FlxCollisionType.NONE to avoid compiler issues for certain platforms (Blackberry).
Update FlxTrail.hx

Moving 'exists = false' until after loading graphic to prevent unnecessary warning from being triggered in FlxSprite.hx.
Merge pull request #697 from SeiferTim/dev

Update FlxTrail.hx
Remove pointless assignments in FlxSprite.draw()
added region size checks for tilemaps

this fixes problem from:
http://forum.haxeflixel.com/help/problem-with-tiled-map-classes-in-flash-target
changed getSpriteSheetFrameKey(), getKeyForSpriteSheetFrames()

this fixes issue described at:
http://forum.haxeflixel.com/haxeflixel-development/pic-flxtilemap-grid-layout-issue-after-upgrading-from-20-to-30
added setColorTransformation() method to FlxSprite

as i've promissed to VictorGrunn
http://forum.haxeflixel.com/help/using-colortransform-with-flxsprites/
Fix issue #699

- angle for FlxPath should be calculated before velocity will be set
  to point
Remove jitter when moving along FlxPath (#699)

- we should round point and node coords
Added function mergeFlxSprite

Quickly draw one FlxSprite on top of another.
Fixed mergeFlxSprite

Maybe I should commit the right version or something oops...
Fix for issue 701 - incorrect set alpha behavior on FlxSpriteGroups
Add Round parameter to FlxAngle.getAngle and use it to calculate angle in FlxPath

- to avoid allocation of two points
Second fix for issue 701
Cleanup in FlxSpriteGroup
Reverting changes to FlxSpriteGroup regarding alpha transforms.

overriding children alpha is as simple as doing:
mySpriteGroup.setAll("alpha", 1);
Fixing compile errors on FlxSpriteGroup
Update FlxPreloader.hx

Fixes the Preloader_gets_stuck_on_Chrome. No reason for disabeling it anymore.