AP TrackerPlugin
* added TrackerPlugin
Merge branch 'master' of github.com:CalVR/calvr
* Added classes for the Observer pattern (labeled as Listener/Shouter as opposed to Subscriber/Publisher).
* Adding CDBApp project to CalVR in support of creating the CvrState class (base State class to be used within CalVR).
* Added the DatabaseHandler and StateManager classes.
* Cleaned up the CvrState class and created a type registration concept within it (instead of defering to the StateManager).
Merge branch 'master' of https://github.com/CalVR/calvr into collab
* Updated cdbapp component references to use the cdb namespace.
* Fixed side-effects caused by asserts in CvrState.
* Added the MetadataState class.
* FileHandler will now load files by either a file path or a MetadataState.
* FileHandler and the FileLoadCallback now return SceneObjects.
* SceneObjects may now be augmented with CvrStates.