OSMF SVN

Pre-PARB metadata changes: Clean up the MetadataNamespace public APIs, hide some internal namespaces. Hide a few other internal APIs.

Fixed injection due to MediaErrorCodes being re arranged.

ChromeLibrary: fixing hints from appearing at the wrong vertical offset, and preventing scrub bar time remaining calculations to go negative.

DVR: extending MediaPlayer to support DVRTrait, and adding more docs.

DVR: adding composite support.

DVR: adding ExcludeClass metadata tag.

DVR: extending implementation details. Extending NetLoader with a time trait factory function, adding a timeTrait property to NetStreamLoadTrait, and having VideoElement use the new property on adding element traits.

Adding 'LocalFacet', removing 'LayoutFacet', and changing layout facets to inherit from LocalFacet.

Pre-PARB metadata changes: Remove ObjectFacet, Facet can be used instead.

Pre-PARB metadata changes: Merge Facet and KeyValueFacet. Default facet uses a Dictionary, clients can extend if they want a different underlying structure. Update TemporalFacet accordingly. Disable some of the TemporalFacet API that's only used for test apps, we need to vet this a bit further. Update unit tests and samples.

Pre-PARB metadata changes: Merge IIdentifier and ObjectIdentifier, rename to FacetKey. Make similar adjustments to TemporalFacet class. Move TemporalFacetEvent to events folder. Update unit tests and samples.