Pathfinder

Hey guys, it's a hot fix for some scaling issues with the navigation algorithm. I tested mainly on very small graphs (2-30 Nodes) and on those you cannot notice performance issues. Only just updated my showcase server with 2600 odes and realized that it takes at some points minutes to calculate the shortest path D: I used a Fibonnaci Heap implementation that is known to speed up pathfinding even further but it was not able to recognize already settled parts of the graph and it'd do millions of iterations instead of thousands. Stepped back to TreeSet for now.