Merge pull request #8 from HaxeFlixel/dev

merge
SimpleRender when blitting now floors instead of rounds (for consistency with everywhere else)
FlxText: fix bug where 0-length FlxText's show improper backgrounds in FlxUIInputText extension
Merge branch 'dev' of http://www.github.com/HaxeFlixel/flixel into dev
FlxText: Added more elaborate comment for bug fix
Fixed capitalization in comment
Merge branch 'bugfix_flxtext' of https://github.com/larsiusprime/HaxeFlixel into dev
FlxText: nasty workaround for initialization with empty strings on flash
Fixed comment on previous commit
Merge branch 'dev' of https://github.com/HaxeFlixel/flixel into dev
Merge pull request #990 from JoeCreates/dev

Fix for rendering issue whereby some sprites positions were rounded instead of floored
FlxPoint: added add() and addPoint()
FlxVector: fix spelling of "subtract" in functions
FlxVector compile fix
No need to implement interface that the super class already implements
FlxG.resetGame(): fix some variables not being reset to default
Update CHANGELOG.md
FlxGamepad: use arrays instead of maps, closes #971

not a good idea to iterate over maps every frame
Fixed gamepad support in Flash.
Adding warning about unnecessary memory allocations in FlxGamepad (flash target only).