Function isClockwise() gives the opposite answer
When I was using the function isClockwise() (in vector2.h) for line-orientation checks, I noticed that it's been incorrect all along.
Currently, the function only called by the Dutra gradient (Ttca::getMovementCostGradient()) which is currently not used, so fixing it will not change any functionality of UMANS right now. However, this could be the one of the problems causing issue #72 (closed).