cleanup STL remesher GUI

Don't set CustomMin and CustomMax to the Min/Max values of the view: it
can be confusing when saving options. Instead, provide buttons in the GUI
to set the custom values to Min/Max if so desired.

always save the surface elements in unv format (not just when the surface is
not part of the boundary of a volume)

small cleanup + don't enter post stuff in select mode at the moment (we
might want to change this if we want to select post-pro views in the future)

instead of drawing in immediate mode (in-between Draw() calls) in HighlightEntity,
just redraw the whole scene. It's slower, but on modern machines it should be OK.
This way we can deal with vertex arrays and mesh highlights easily. I will revert
this change if too many people complain...

- made meshed curves/surfaces selectable with the mouse
- better selection algorithm (use depth info to find the "closest" match)

re-add the WIN32 test (the add_fd code is not ready)

fix problem with redefinition of log2 on cygwin (Laurent told me that he had
a warning on Mac 10.3 also)

"./configure --disable-contrib" to compile a vanilla version of Gmsh
without any external code

forgot make depend in NR

We cannot distribute Metis until we ask permission to Karypis.

JF: tu t'en charges ?

make depend

moving all external code to contrib subdirectory

apply patch from the Debian people

mention the variables file at the end of the configuration process

use it now with -partition N for N partitions
only works with tets and triangles
output should be added (useless for now)

mention bug on Windows without Cygwin when reading binary post-pro files

explain #list[]

Fixed horrible performance of vertex array creation on Windows for
very large post-pro views (> 1 millon triangles). The bottleneck is
the memory reallocation, which is 100 (?) times slower than on
Linux/Mac. Introduced some simple heuristics to estimate how many
primitives will be displayed. A prepro pass (like for smooth normals)
would be a more elegant solution.

use the autoconf uname