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)

fix reload

use time vals if avail

cleanups

reinterfaced adaptive views with new post-pro

upgraded all plugins to work with the new post-pro.

This is done "cheaply" for now, by only using old-style list-based datasets.
Taking advantage of the abstraction (so that we can use the plugins on all
datasets) will require more work. The hooks for transparent data translation
are in place, but the actual translation has not been implemented yet.

- fixed 2d time plots
- better 2d space plots when absissa not monotone