removed global THEM

(once more step towards nicer integration of old GEO stuff)

add option to test auto skin stuff

add option to test automatic skin stuff

add experimental support for automatic on-the-fly boundary computation
in vertex arrays

- don't force show geom surf/vol if we have a mesh
- removed unused stuff in VertexArray before moving to set<ElementData> for
  auto boundary creation

only make tri unique in 3d

manage GModel::list automatically (like PView::list)

fix BDF small field export on Windows (apparently Windows does not conform
to ANSI C and uses 3 digits in %e instead of 2)

remove dependency on FLTK 1.1.7 (replace call to Fl::screen_xywh with call to Fl::w)

compatibility fix: make arrows scale like in the old version

better normals

- print extra info for faces and volumes
- added couple of examples

new Mesh.RefineSteps to control how many refinement steps we perform in
2D MeshAdapt-based algorithms

- don't use vertex arrays for quads anymore (they are wrong for non-plane
quad faces): just use triangles everywhere

- removed _links in PView

- various small cleanups

postbuild not necessary anymore on mac

add option to center glyphs (arrows, labels)

- fix max in scale for external view
- fix vector scaling

fix tensor simplex bug

fix

fix

- fix crash in Plugin(MakeSimplex)
- fix main bbox computation when one view has an empty bbox

tweak 2d graph + other small fixes

all that was there is back (can be enhanced later)

start reintro high order rep

fix crash in batch mode

don't remove duplicates when picking individual elements (since some
elements might then never have a pickable entity)

rewrote vertex array code for meshes in the same way we do it now for
post-processing (much simpler, pretty much same speed, and takes a bit
less memory)