Attach to vehicles

#733 

Attach IR Strobes to Vehicles (AKA Tactical duct-tape)

Allows attaching stuff to vehicles (same items as to players).
Can attach multiple objects to a vehicle.  
When detaching from vehicles it will just detach whatever you are closest to.

Uses the Explosive placement to get a starting position of the item.
It then uses lineIntersectsWith to try and find where the hull starts, so it can attach the light directly.

![2014-12-06_00006](https://cloud.githubusercontent.com/assets/9376747/5329944/4a8de264-7d91-11e4-94dc-d86b4dc8df64.jpg)


Problems:
A light attached to a turret won't rotate with it.  Not sure if fixable.