Server: Minor optimization of pathfinding algorithm.

[plomrogue] / TODO

Next planned steps in plomrogue development:

IN GENERAL:

- expand use of hardcoded_strings module(s)

BOTH SERVER/CLIENT:

- make server and client communicate by specific world state info requests 
  in server/out, replacing server/worldstate

CLIENT:

- re-work unnecessary complex command / keybinding / server message mapping