fixed dijkstra memleak

new dijkstra interfaces and abort options
refactored all files accordingly
enable logging via compile-time defines

grid/walk/GridWalkPathControl.h

@@ -45,7 +45,7 @@ public:
 		gen.seed(1234);
 
 		// build all shortest path to reach th target
-		dijkstra.build(target, target, acc);
+		dijkstra.build(&target, acc);
 
 		// attach a corresponding weight-information to each user-grid-node
 		for (T& node : grid) {