Update space_iterate.c

** Autopilot will not slow down on approach, you can approach at any speed and it will drop you out of warp properly.
** Autopilot drops you out of warp ~2000 SU from the target unless you slew 2000 su using the slew command.
** Hooks for automation.  I am not sharing my bot code. 
** You can not exceed warp_cruise if you are cloaked.
** Changed turn ratio. Still playing with numbers but this feels good so far.
** up_warp_max and up_impulse_max now return the maximum the object can go with given allocations. Actual max is defined in the ship specs.