Updated angle of attack
Added relative airmass velocity to AOA calculation

The Angle of Attack is now calculated with respect to the airmass velocity.
Added conceptual documentation.
Basic flight drag now works
Flight now possible! Lift property added.

* Lift is now properly calculated, allowing for *rough* flight
* Force measurement changed to N/H for lift and drag
* Lift coefficient is extremely rough estimate
Restored simple banked turning
Set directional velocity for objects

Objects' velocity is now slightly based on the direction they are pointing.
They can no longer fly 'sideways'
Merge branch 'master' into flighttesting

Conflicts:
	Unity Free Flight/Assets/UnityFreeFlight/simpleflight.cs