OSMF SVN

Initial commit of refactored metadata API. Note that this is the first step in a major, multi-step refactoring, so there may be some stability issues until the last step is made. Highlights of the changes:
- Simpify metadata API from Metadata + Facet + FacetKey, to a single Metadata class that exposes a key-value pair based API, plus change events.
- Modify MediaResourceBase and MediaElement to expose add/remove/get methods for metadata, rather than a singular metadata property. MediaElement dispatches change events via the new MediaElementEvent.
- Rename/Refactor TemporalFacet to TimelineMetadata (ditto for event class), which extends Metadata and works with a generic TimelineMarker class to represent a marker on the media's timeline.
- Remove MetadataNamespaces, the properties behind these client-facing namespaces (which previously were set through facets) can now be set through strongly-typed properties on MediaResourcBase, URLResource, or StreamingURLResource. This includes media type, MIME type, subclip points, DRM metadata, and more.
- Move CuePoint and CuePointType to metadata package. CuePoint now subclasses TimelineMarker.

Removing obsolete classes.

Updating syndication library. Atom support is complete.

Fixed NetLoader's regexpression , which was failing for certain urls with extensions.

Temporal trait wasn't getting added to video element if it didn't come from the NetLoader.

Fixed Integration tests that were failing due to DRM. Plugin tests are still failing due to plugins sitting on remote servers that need to be updated.

DVR: fix for FM-465.

DVR, CR feedback: change 'retreiver' to 'retriever'.

DVR: removing lingering imports.

DVR: unit tests, continued.