dc04def Pass view-relative teleport flags through in 1.9->1.8 (#719)

1.8 handles the rotation-relative position flags (0x08/0x10) natively, and resolving them against the tracked rotation snaps the camera to a stale look on every teleport. Keep the rotation bits and their deltas on the wire and only resolve the position bits.

Since the client applies kept deltas to its own live look, its teleport confirm echoes a rotation the tracker cannot predict - match those confirms on position only and adopt the echoed rotation.