(CARD) Naval AI

Allows for AI-control.


 * Broadside minimum distance - range below which it will turn vessel away from target. Above this range up to Enter range is the active broadsiding range.
 * Enter broadside below this distance - range below which it actively turn the vessel to nominal broadside angle relative straight at target.
 * Leave broadside above this distance - range beyond which it will turn vessel back toward target.
 * Nominal broadside angle - 0 degrees is straight at the target, 90 degrees circles the target. Less approaches, more retreats.
 * Idle Approach Distance - prevent AI from clustering friendly ships together resulting in collisions.
 * Turning Circle - minimum radius ship can turn. Underestimating can produce bizarre AI behaviour as it plots paths the ship cannot follow.
 * Depth Requirement - helps avoid shallows where ship may get stuck
 * Disable Reverse - sometimes AI gets silly. Happens more if vessel cannot turn well.  This may help.