Decelerate faster when mass-locked

Experimental - give more chance to assess and react to NPC packs before
reaching laser range - as you would if not using torus drive.
Update torus drive to be even faster if a long way from nearest object

Very experimental - based on old suggestion at
http://aegidian.org/bb/viewtopic.php?p=185086#p185086
Can be disabled easily by changing the OO_VARIABLE_TORUS_SPEED #define

Should make it a bit more practical to use the OUTER_SYSTEM and
OUTER_SYSTEM_OFFPLANE locations without requiring excessive flight time