Fixed AudioManager bugs:
- Music loops correctly if sequence has only a length of 1.
- Sounds are stopped before they are played again.
- Can now play pitchable sounds.
- Added get methods for Sounds and Musics.
Tetragon Engine version: 1.2.0 build #12840 Lalande
Removed Debug.log call from Music.
Tetragon Engine version: 1.2.0 build #12842 Lalande
Added ListSoundsCommand.
Added toggleMusicVolume() to AM.
Fixed bug in AM related to BasicSound objects.
Added BasicButton class.
Added back the optional screen background functionality to
ScreenManager.
Fixed a bug in StartupApplicationCommand that would repeadedly call
finalize() in case several preloaded resources refer to other resources
that have (not yet) been defined.
Added some helpful log() to Render2D.
Added support for preprocessing resources to the resource management.
Resources defined in the resource index can now be specified in a
<preprocess> tag and are then processed automatically with their
dedicated resource processor. This allows one to define resources that
should/need to be processed without the need to change code.

Currently the processing is done before the screen manager is started.
Optimally this should take place right aftrer loading but Stage3D is not
ready early enough for that and texture resources require Stage3D to be
initialized to process them.
Changed the implementation of screen background in the screen manager to
allow using backgrounds used with Render2D.
Changes in Render2D: Added new View2D base class that extends Sprite2D,
renamed former View2D class to RootView2D which has extra functionality
for an optional root background. This way the new View2D class can serve
as a base class for Render2D view objects that adheres to IView.
Equipped the resource index with a method to return an array of all
resources of a specific datatype.
Added MaskedSprite2D class.
Prevented an exception in RenderSupport3D, instead logs a warning now.
Improved BaseClass.
Fix in Render2D to resize background to stage2D dimensions.
Compiled SWC.
- Added static methods fromBitmapData() and fromDisplayObject() to
Image2D.
- Made ScreenBackground class to auto-generate screenCover and/or
render2DBackground on demand from the nativeBackground.