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.  
Ok! Looks like pushing these vectors is already done, actually. I didn't have the context lines expanded in the patch to see them. The note about documentation could be important though.