Merge pull request #123 from virtual-world-framework/Ken-Art

Ken McClure: Update to scene.dae and terrain.jpg and terrain_spec.jpg.  ...
Move the scenario files into their own directory.
Merge pull request #128 from virtual-world-framework/scenario2

Move the scenario files into their own directory.
Add the intro screen scenario.
Add the ability to fire triggers when specific types of blocks are
added or removed, and use it to fire off VO.
Ken McClure: update to scene.dae....added in smalls rocks down the canyon pathway.  Updated rubble.jpg and rubble_nrm.jpg.