Vizard-PPT conversion

[Gladsomebeast]

With the viztracker module, people often code in a "reset" to aligne the orientation sensors coordinate system with PPT cooreinate system. It works by facing the orientation sensor in the postive Z direction of PPT, then pressing some key on the keyboard. Usualy this key is 'r' or alt-r.

Its easy to code a reset yourself if you want to do that. On a key press, grab the current raw yaw value of orientation sensor and subtract all subsequent yaw readings from this saved value before applying orientation to view.