add big warning for Delaunay algo

small cleanups for 2.0.8

for akash: if there are no elements in a .msh file, create a geometry vertex
for each mesh vertex

prepare for post-pro changes by moving all post-pro stuff in separate directory

- added option to print all latex strings as equations
- fixed constness of prototype in autocad/message.c (thx to oshima@eng.niigata-u.ac.jp)

fix side effects from new font size computation

by default, choose GUI fontsize automatically (so that we use larger fonts
by default on all these new fancy displays with huge resolutions)

fix isolated </p>

fix mesh algo #defines for back compat

tweak labels

enable new Delaunay for plane surfaces

experimental: don't use it for now

fix fouriermodel depend

replaced non-scalable bitmaps labels with scalable vector labels

- better tol in checkMeshCoherence()

additional patch from oshima@eng.niigata-u.ac.jp

use C++ for all compilation tests

warning->error when trying to assign explicit reg ids in extrusions
+ add note in doc for this

2nd part of streamline patch from oshima@eng.niigata-u.ac.jp

add back/forward step buttons (patch from oshima@eng.niigata-u.ac.jp)

select time step

support groups of nodes for physical groups (gor Guillaume)

implemented "Save groups for nodes" for unv

format needs to be verified

- prepare group of nodes in UNV (for Guillaume)
- prepare delaunay for connected volumes
- test 2nd patch from Michel for phase1() extrusion