Add and update dependency version

[CrazyFlasher]

Currently there is a little bit mess with extension's versions.
I am trying to organize my project dependencies version and it would be cool, if you would track version somewhere.

[IonSwitz]

Sorry, I won't be able to do something like that that makes sense. What I used to do, back when I was still developing games using Starling was to tag the directory where I downloaded the Starling source version with a timestamp, so "Starling_19Dec2014" would hold one version, etc.

Since quite a few of these extensions and even the base Starling framework isn't continously released with a proper "one version update for each GitHub commit", there is no way to get this fully functional.