First cut at HMD Tools window

Included:
* First cut at HMD tools window and better oculus startup support.
* fixes bug where camera is broken when leaving VR mode

Details in HMD Tools:
* HMD Tools dialog with enter/leave HMD mode buttons and basic screen debugging.
* finds which display on a multi-monitor system the Oculus Rift is.
* when entering HMD Mode - moves the main window to that screen, enters VR mode, enters full screen, centers mouse on HMD screen so that reticle works.
* when leaving HMD Mode - moves the main window to the primary/previous screen, leaves VR mode, leaves full screen, centers mouse on main app screen.
* HMD Tools supports hide/show via META+H (Mac: CTRL+H, Windows: ALT+H)
* When HMD Tools dialog is hidden or shown, cursor is snapped to the dialog on show, to app on hide.
* works with Mirrored mode or multi-display mode
* handles case of no rift by switching between full screen/non-full screen.

Still to do:
* I would like to improve the case of connecting/disconnecting a Rift while the application is running. Right now some aspects of the Rift SDK gets confused in this case.
* Would like to add hot keys for enter/leave HMD mode
* Would like to change the enter/leave to a single button instead of two.
* Would like to add a hot key for enter/leave mode.
* Would like to implement support for preventing you from getting the HMD Tools "lost" on the Rift Screen. Making sure that it is always displayed on either the Primary screen or the last non-Rift screen you had the application on.


this fixes the broken camera when leaving VR mode - basically the _myCamera had residual HMD position and rotation information.