* Fixed bug with input devices that where added, removed then re-added.
The default mappings were being ignored on the second add.
* Fixed potential crash when hardware inputPlugin device poses were polled from the JavaScript thread
by taking the UserInputManager lock during pluginUpdate.
* Renamed Controller.Hardware.Vive.LB & RB to LeftGrip and RightGrip, to better match Oculus touch.
* Updated resource/controller/vive.json to reflect this new mapping.
* Exposed touch pad capacitive touch events to JavaScript as
Controller.Hardware.Vive.LSTouch and RSTouch.
* Added viveTouchpadTest.js script to test LSTouch and RSTouch events.
