First cut of Spacebar-to-fly with Oculus and Faceshift, stabilize Faceshift head jittering

This adds to hydraMove.js the ability to fly/move by pressing the spacebar and moving/turning your head, for both Faceshift and the Oculus DK2.  I will keep tweaking and tuning, please send me feedback.    Rotating your head with spacebar pressed will slowly turn in the direction you are rotating, allowing you to turn all the way around.  Leaning your head forward and back or side to side will move/fly you in that direction. 

Also the movement of the head as detected by Faceshift is now velocity filtered, so that when you are still your 1P view should be much more (pleasantly) stable.