LumenRT Update 4 Tech Preview - Updated

Bumped Jan 4, 2018:

Here is a link to the final LumenRT Update 4 Release Candidate - Build 0488.  This is probably going to be the final production release.  Contains bug fixes for stalling vehicles and install issues.

New features include:

- 180 degree pano output

- 360 panoramic image sequence output (for point to point walk-path style animations)

- Improved stereo display support

- Better 3SM mesh handling (clipping and url-based 3SM's)

- A number of bug fixes