Hand trigger presses are not reported on k_EButton_Axis2

SteamVR reports the hand trigger on k_EButton_Axis2, as well as on k_EButton_Grip for compatibility with SteamVR games. In Vivecraft we use the former as it's technically the correct enum to use for this button (it is an axis, after all), and the result is the hand trigger being non-functional as a button (the axis still works).

If you could report the button on both to match SteamVR's behavior, it would be greatly appreciated and enhance OpenComposite's game compatibility.

I should also note we are reading button inputs via VREvent_ButtonPress and friends.