Merge pull request #1331 from sgrenier/next

Changed Terrain to use material files
Fixed memory leak in AudioListener and Camera
Merge branch 'next' of https://github.com/blackberry/GamePlay into next
Ensure xcopy only copies shader files with a more recent date to not clobber existing files that a user may have modified.
Merge pull request #1333 from seanpaultaylor/next

Ensure xcopy only copies shader files with a more recent date to not clobber existing files that a user may have modified.
Merge pull request #1332 from dgough/next

Next
Changed and simplified handling of custom material auto bindings by adding a new abstract class RenderState::AutoBindingResolver.
Games can now simply extend this class and implement the one virtual function in it (resolveAutoBinding) to provide support for custom material auto bindings.