* All platforms now use asset configuration files. Subclasses of DesktopAssetManager no longer required.
* Added general asset config file which is included by all
* JmeSystemDelegate now always returns DesktopAssetManager
* JmeSystem is now responsible for providing the platform-specific asset config path
* Deprecate JmeSystem.createImageRaster(), it is simpler to create a DefaultImageRaster
Also changed JmeAndroidSystem to store the view instead of the activity.
When users call JmeSystem.showSoftKeyboard(true), the default Android soft keyboard is displayed and any key presses are sent to jME as touch events. Key events are also generated so the user can use the same key listeners as Desktop to keep the user code common between Desktop and Android platforms.
* Unified all renderers into common class 'ALAudioRenderer'
* LWJGL and Android now implement the AL / ALC / EFX interfaces to provide a common OpenAL backend for jME
* Added support for OpenAL Soft "Pause Device" extension, which allows the engine to pause the context while running in the background (currently requires OpenAL soft 1.16 and thus is Android only feature)
