Pathfinding Corrections And Cleanup

Though the branch is titled "pathfindingoverhaul" this is more of a cleanup that adds features and fixes several problems.

There will be another "iteration" of this later after I do some tinkering with AIWander and fix some more stuff.

Fixes algorithm problems (thanks to Chris), cleans up pathfinding and all AI package implementations, adds a new function for clearing the path (which removes the old messy method of making a new pathfinding object), allows for selection of whether or not to use shortcuts (ie: cast a ray) (this is for AIWander mainly as it doesn't but all other packages do), fixed the problem with the guard going to far into the players starting room on the ship, and finally fixed the problem with AIWander picking nodes that it cannot reach (ie: behind a wall that requires entering the cell from a specific location, like the one in between the Census and Excise offices).