--Added CollisionWorld as superclass of DiscreteDynamicsWorld.
--Added CollisionWorld::contactTest().  Note that this depends on a modified AwayPhysics.
--Fixed DiscreteDynamicsWorld::set gravity() to behave the same for both the native lib and the default (AwayPhysics) lib.
Modified declarations in debug.h to eliminate errors generated by Xcode 5.0.
Adding some cruft to .gitignore
Cleaned up some old stupid nonsense with CollisionObject's wrapped AWP object.  Don't know why this solution didn't occur to me earlier, but I'm always happy to get rid of old stupid code.  OOP, FTW!
Changing native source file extensions from .mm to .cpp in preparation for Android build.
-Added Android support (requires the Android NDK)
-Changed some link types for the default lib to make Android ANE work.  Did not yet test this with iPad hardware!
-Updated required AIR SDK version to 3.9
-Got rid of bullet-ane Xcode workspace because the BulletANE Xcode project contains the required Bullet projects anyway.
-Simplified Bullet SVN checkout script
Updated the README
xcodebuild from command line wasn't working right, so I reverted to building the iOS part from the Xcode GUI.  This is reflected in the README.
Merge branch 'develop'
Main new feature is Android support.