Inlined some method calls in me.TMXOrthogonalRenderer.drawTileLayer

A couple of method calls in drawTileLayer were creating garbage unnecessarily, i.e. `me.Vector2d` objects which were immediately released.  Inlining these methods gives us slightly less elegant code but saves us some cycles on garbage collection.  
Are these vectors used later? Certainly they continue to be referenced by this layer, so it's not exactly safe to push them back into the pool until the layer itself is removed from the scene and destroyed... Same with the other changes in this file. I guess there's a better way to do this, or just leave it as it was (no pool).