dijkstra is now bleching fast

deleting from the grid is now bleaching fast
added new helper methods
many new test-cases
many new methods for geo classes and others
added a bunch of new grid-walkers

grid/walk/GridWalkState.h

@@ -2,6 +2,7 @@
 #define GRIDWALKSTATE_H
 
 #include "../../geo/Heading.h"
+#include "../../geo/Point3.h"
 
 template <typename T> struct GridWalkState {
 
@@ -14,6 +15,8 @@ template <typename T> struct GridWalkState {
 	/** empty ctor */
 	GridWalkState() : node(nullptr), heading(0) {;}
 
+	Point3 avg = Point3(0,0,0);
+
 	/** ctor with user-node and heading */
 	GridWalkState(const T* node, const Heading heading) : node(node), heading(heading) {;}