start reducing header pollution (removed Gmsh.h + cleaned up GModel & co)

more Visual C++ work

more work for Visual C++

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

start opencascade integration

fix missing SIGN in NR

moved most OS-dependent functions in OS.cpp

Rewrote the background mesh code to use the new post-pro octree instead
of the old brick stuff. It's 100x faster ;-)

- new button under the graphic window to temporarily disable mouse
  selection (speeds-up redrawing of very large models + permits to
  rotate/zoom-in a model in selection mode even when the whole screen
  is full of selectable entities--e.g. a surface mesh)

- new "lasso" selection mode (to select entities using the same kind
  of lasso as the lasso zoom: just Ctrl+click, then drag the mouse in
  selection mode; the shortcuts are the same as for the lasso zoom)

- it is now possible to unselect entities using the middle mouse button
  (only for the creation of physicals at the moment; not sure if it's
  useful in the other cases)

- new button in visibility browser to invert the current selection
  (very useful e.g. when multiple physical entities are associated
  with a given elementary entity, in order to "peel" away the model
  when adding new physicals; cf. philou)

- changed meaning of Escape shortcut (cancel lasso or toggle mouse
  selection) + restore standard fltk Escape handling for all dialog
  windows

- updated copyright string

- new mesh label mode (coordinates); all label types are now also
  available for mesh vertices

- added option in 'Print Option' dialog to disable printing of help
  strings

- added a comment string with the date when creating a new file

- new snapping grid for adding points in the GUI

make depend

make depend

First batch of changes so that we can compile the code on windows
without cygwin. With these changes gmsh compiles and runs cleanly
without solver/jpeg/png/triangle/netgen/gsl support.

fix memory leak + missing depend

removed unused stuff + handle SURF_DISCRETE in MeshDiscreteSurface

copyright update

-D_BIG_ENDIAN conflicts on SunOS -> changed our last -D_XXX definitions to
-DHAVE_XXX

Update copyright notice

main() should return zero after a successful run

Fix whitespace in copyright headers

Add missing copyright headers

Indented all source files using utils/gmshindent

This is a pretty big commit.

- The Numerical Recipes routines have been moved to their own
subdirectory: NR/

- These routines are now completely optional. Configure will
determine if they have to be compiled in (if it's a non-free version
of Gmsh) or if we should use the GSL routines instead.

- The GSL routines are there. Well, sort of. The SVD stuff works
great, but the minimization routines still need more work. The whole
infrastructure is there, though: we can already compile a fully GPL
compliant version of Gmsh by removing the NR subdirectory (or by
specifying --enable-gsl to configure).

- I also simplified the options passed to the compiler (OPTIM and
FLAGS).

That's all for today folks...

New makefile system based on autoconf. Only tested on Linux right now.

Updated copyright