Added a removeEventListener in the onAddedToStage method.
Merge pull request #215 from FrancescoMaisto/patch-1

Added a removeEventListener in the onAddedToStage method.
Add support for filter subclasses changing the location of shader attributes
added 'RectangleUtil.fit' method
now forcing correct stage scalemode and align
simplified demo startup code slightly and added more documentation
fixed wrong alpha for cached filters (closes #213)
fixed: now applying skew after scaling (closes #212)
fixed typo
forgot to set mX and mY ... (refs #212)
Merge branch 'master' of git://github.com/alexmac/StarlingTweaks into alexmac-master
renamed members, added some doc-comments
extended dispose documentation
Replacing multiple eventListeners with one

Hi!
I am proposing a small optimization change to the demo source where instead of adding an eventListener for each button of the main menu, only one eventListener is added to the 'Game.as' constructor. Also I am adding a condition to the onButtonTriggered method to deal with events generated by the back button in the 'Scene.as' class. This will also allow to simplify the 'Scene.as' class, by removing its own onBackButtonTriggered method. (I am going to edit Scene.as too, to show how).
Removed the onBackButtonTriggered method

Here I removed the onBackButtonTriggered method, as in the proposed change a single onBackButtonTriggered method in 'Game.as' is handling the triggering of the Back Button too. Also removed the public constant "CLOSING" as it's no longer necessary.
Merge pull request #221 from FrancescoMaisto/patch-2

Replacing multiple eventListeners with one
removed references to Scene.CLOSING
removed an obsolete call
added another workaround for constrained mode vs. viewPort bounds
now toggling stats display when user touches driver info