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

tests/grid/TestWalk.cpp

@@ -12,7 +12,7 @@
 #include "../../grid/walk/GridWalkWeighted.h"
 #include "../../grid/walk/GridWalkLightAtTheEndOfTheTunnel.h"
 
-TEST(Walk, plot) {
+TEST(Walk, DISABLED_plot) {
 
 	Grid<GP> g(20);
 	GridFactory<GP> gf(g);