Get rid of create_triangulation_compatibility in the UNV reader.

Get rid of create_triangulation_compatibility in the UNV reader.

This case is interesting since the current code only works by coincidence. Our
test files have vertices numbered like

    2 ---- 3
    |      |
    |      |
    1 ---- 0

which we read in in the old-style (UCD) numbering, which is like mirroring
across the y-axis. This causes all the cells to have a negative measure (but they
aren't pinched). GridReordering then fixes this by swapping vertices 1 and 3 of
every single cell - i.e., adding another -1 factor to the measure, which now
causes all cells to have positive measure. Something similar happens in 3D.

As far as I can tell there is no widely accepted node numbering for UNV like
there is for everything else so I am going by what Salome generates. Since we
now use their numbering directly (instead of something that worked by
coincidence) the output files are slightly different but all cells do end up
looking correct (nothing is twisted when we visualize with VTK).