OSMF SVN

Third phase HDS refactoring
- LBA reactivated (VOD and LIVE)
- HTTPStreamingF4FMixer updated to use FLV classes inside org.osmf.net.httpstreaming.flv packages
- minor modifications in order to minimize the updates of mixer internal buffers ( the internal buffers are reallocated only after we use at least half of their content)
- updated the mixing algorithm inside onMainTimer in HTTPNetStream
- mixer class is responsible to signal that is missing audio or video data
- update HTTPNetStream to wait for alternative audio initialization before it actually start playing data

IMPACT:
- no public API was affected

*NOTES*
- we still have unit tests and integration tests which fail

Modified the HSF4FIndexHandler - it now updates the bootstrap regularly (approx. each fragment) in both Play and Paused states.

Fix for FM-1295 (http://bugs.adobe.com/jira/browse/FM-1295)

NOTE
When dealing with protected content, the drm side car information was loaded only from drmContentData property of StreamingURLResource. This was particularly bad for MBR content, where the drm information was loaded to late and could put the MediaElement in an unloaded and back in a loaded state.

Now we are looking for drm information in the following order
- in drmContentData 
- in DRM namespace on the resource ( here we are trying to obtain the drm metadata for the stream indicated by initial index, and if we don't succeed then we are using an available information )

Fix for FM-1293 (http://bugs.adobe.com/jira/browse/FM-1293)
- DVR information is now propagated only from main stream ( never from alternate audio stream)

- partial reactivation of LBA

Fix for FM-1292 ( http://bugs.adobe.com/jira/browse/FM-1292 )
- HTTPStreamSourceHandler is now queuing all index loads request and process them
- removed also some comments and unused code

Second phase HDS refactoring
- added a factory class for streaming objects ( HTTPStreamingFactory ) which any HDS implementation must extend
- removed mixing code from HTTPStreamingFileHandlerBase and its derived classes
- updated private events related to HDS to make them more consistent
- adding source handler to manage both index handler and file handler
- removed enhanced seeking from HTTPNetStream ( temporarly )
- removed permanently MBR logic from HTTPNetStream

IMPACT:
- no public API was affected

*NOTES*
- LBA is still not working
- unit tests and integration tests fail
- DO NOT USE IT EXCEPT IF YOU ARE TESTING THIS

First phase HDS refactoring - extracting the URLStream downloaded in a separate class.
- *NOTE* LBA is not working anymore

HelloWorld9.as internal assets add

Fix RTE when switching between stream with/without LBA ( when stream in unloaded )

Attempt to improve playback experience on HDS late-binding on audio