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

math/DrawList.h

@@ -4,6 +4,8 @@
 #include <vector>
 #include <random>
 
+#include <KLib/Assertions.h>
+
 /**
  * add elements of a certain probability
  * and randomly draw from them
@@ -68,6 +70,11 @@ public:
 
 		// binary search for the matching entry O(log(n))
 		const auto tmp = std::lower_bound(elements.begin(), elements.end(), rndVal);
+
+		// sanity check
+		_assertFalse(tmp == elements.end(), "draw() did not find a valid element");
+
+		// done
 		return (*tmp).element;
 
 	}