Rotate the player's avatar to face forwards when in FPV. Add a state to keep track of the player's interactions.

[Gigabyte5671]

The PR contains two unrelated changes (oops).

1. When in first-person view, rotate the player's avatar so that it faces the same direction that they are looking.
2. Add a state to keep track of the player's interactions (relates to A new state needs to be added to keep track of the player's sitting/interactions. #143).