EMI: Implement head tracking.
EMI: Implement head limits.
EMI: Fixed Actor::getWorldPosition calculating the world transform incorrectly for attached actors.
EMI: Continuously update the look at vector when looking at an actor.
Merge pull request #947 from Akz-/emi-head-rebase2

EMI: Implement head tracking
EMI: Fix attached actor's rotation.
EMI: Fix the actor's position after attach.
EMI: Fix the rotation after detaching actors.
EMI: Rework getFinalMatrix and getRotation quat to remove duplicate code.
Actor Testing - REMOVE ME.