Quad Refinement doesn't preserve orientation

[craffael]

If we refine the this mesh with MeshHierarchy::RefineRegular(), the refined mesh contains quads with positive and negative orientation even though the original file had only positive orientations.

[hiptmair]

Orientations are not preserved by refinement and it was never supposed to do so, because this was not part of the specification. It would be a very big effort to change this, and error prone, moreover.

If this is a problem for visualization, then it has to be fixed by correction for different orientations a posteriori.