* UI outline and dropshadow shaders respond properly to alpha changes, now.

* Added a UI dropshadow outline shader.
* Mesh will no longer jump forward if time scale is being ignored and window goes out of focus when application is told not to run in the background, then comes back in focus.
* Added an experimental unlit & UI pixel snap shader.
* Added a "snap to grid" vertex mod to the vertex mod sample script.