OSMF SVN

Fix bug ZE-34 and ZE-29. They are all about a 4-5 seconds delay of the audio when the content is DRM protected. It turns out to be a bug with HTTPNetStream, or more precisely a bug with the SVN creating patch feature.

PARB feedback: Rename wrappedElement to proxiedElement, make constructor param optional.

Remove obsolete import.

Remove obsolete test class.

PARB feedback: Remove ContentElement and ContentLoader, refactor common image/SWF code into a non-public utility class.

[DVR proto] Adding LayoutProperties straw man, plus a usage sample.

[DVR proto] Integrating trunk changes.

Removing lingering debug trace.

PARB feedback: Remove swfRoot property from SWFElement, it's already accessible through the DisplayObjectTrait.

PARB feedback: Allow MediaElement subclass constructors to have default params. This involved moving the ILoader param to the second param, and providing a default when no loader is provided. For subclasses (like VideoElement) for which multiple loader types are supported, the implementation now chooses the appropriate one based on the resource type.