Merged requested to merge andrew.wilson/iMSTK:VRFixAndSuturingTest into master
- Fix VR controls as two grips and two triggers couldn't be pressed at once.
- Update camera movement but its still not correct.
- Fix release when grasping.
- Move FPS counter down to imstkViewer base to be used by all viewers (possible after ECS move).
- Introduce VRLapToolControl example to tie knots. Spheres can be used as hands, and PbdObjectGrasping reused to grasp lap tools with sphere hands!
Note: Did this one in my free time last weekend to play around with VR. Note: We don't have controller mappings for headsets other than Oculus at the moment.