Addresses reports R718, R772.1, <Someone> P's extra move bug
- when there is a previously seen path or a straight path, always take it
- incorporate fix to ensure no extra "." turn at the end of traveling, but
still avoid stepping into traps/pools, et al
- include a general "G"-command (and travel) fix to avoid stepping in
known pools/lava while blind
- when there is no such path, "guess" at a path by finding an intermediate
location that the hero couldsee that is closest to the actual goal, the
intermediate goal is re-determined at each step
- when Blind, don't use couldsee for determining straight paths, just direction
- do not consider doors or most boulders obstacles for picking travel
paths, test_move has a new mode to differentiate this case from the regular
test case
- don't include known trap locations in the travel path, avoids unnecessary
stops along the way, and usually doesn't affect the path length
- reformatted the code a bit so I could follow it