many changes and updates

- changed the wifi-estimation api
- adjusted test-cases
- worked on grid-bulding and grid-importance
- new walking modules
- fixed some minor issues

grid/walk/v2/modules/WalkModuleNodeImportance.h

@@ -44,8 +44,8 @@ public:
 		(void) curNode;
 
 		const double prob = potentialNode.getNavImportance();
-		return std::pow(prob, 10);
-		//return prob;
+		//return std::pow(prob, 10);
+		return prob;
 
 	}