* rulesets/basic/mind/Knowledge.py: Fix nasty problem caused because
the default arguments to constructor meant that all knowledge
was shared between all entities, causing invalid pointers in
the wrong places.
* rulesets/MemMap.h: Add const to find method, as it should be.
* modules/Location.cpp, modules/Location.h: Add new function for
usefully calculating the distance vector of another entity.
* tests/distancetest.cpp: Update test to check new distance
function.
* rulesets/Python_API.cpp: Make the new distance vector function
available to python rather than the relative postion function.
* rulesets/basic/mind/Knowledge.py, rulesets/basic/mind/NPCMind.py:
Ensure that Knowledge really does handle arbitrary triples.
* rulesets/basic/mind/goals/common/misc_goal.py: Add new version
of transaction goal for transactions for hirelings.
* rulesets/basic/mind/goals/humanoid/transaction.py: Complete
the implementation of the trigger goal for hirelings.
* rulesets/mason/define_world.py: Move the mercenaries closer to
origin for debugging.
