Prepare for commercial release

Save the chosen FLTK theme in the per-session resources

Fix a couple of bugs for 2nd order elements. Seems to work OK for 2D
meshes now. 3D is still kinda flaky, and extrusion is not implemented.

- add PNG check in Get_BuildOptions()
- move "make doc" to top-level Makefile
- better "make purge"

Corrections apres relecture / part 1

Added shortcuts.texi

Fix whitespace in copyright headers

pretty print build options

pretty print build options

Make headers self-contained

add progname in -info

GPL -> General Public License

License stuff

Indented all source files using utils/gmshindent

Add some indent directives

Clean up VERSION_FLAGS and OS_FLAGS (use HAVE_FLTK instead of _FLTK,
remove _BLACKBOX, etc.)

Updated copyright

Introduce OpenGL display lists for drawing meshes. Does not seem to
work much faster on my machine, though.

Fix make source

- Cosmetic changes in 'File->Save as' menu
- 'flattened geometry' -> 'unrolled geometry'

Interface polish (buttons should not be resized when the size of the window is changed);
gl2ps update (not finished);

Intagration of Jonathan Shewchuk's Triangle as an alternative high performance 2D Delaunay algorithm