Oculus Touch controller update

Here's a little update for the demo concerning Oculus Touch controllers:

- Grabbing weapons with grip: press and hold the grip button, release to drop
- Grabbing and holding attachments, weapon parts and grenades: trigger or grip buttons , you can choose between the two according to your personal preference

Hand gestures are still WiP for Touch controllers.

Let us know if you'd like to see toggleable press-and-hold vs. press-to-grab-press-to-drop option implemented by leaving a comment under this announcement. :wink: