fixed bug for multi timestep tets in searchScalar

- removed all the crappy STL code and rewrote it using JF's POLY_rep
  class

- generalized POLY_rep so that we can use the polygonal discretization
  as a surface mesh, and mesh in 3D afterwards. I.e., we can now take
  an input triangulation (a single surface in STL format, multiple
  surfaces in STL format, one or more surfaces defined using the new
  "Discrete Surface" commands), and generate a 3D mesh that uses it. We
  could in theory even mix triangulated and "normal" surfaces in the
  same geometry, but nothing is done at the moment to ensure that the
  mesh at the interfaces would match (if it does, it actually works
  very nicely)

- new STL mesh output format to export a surface mesh as a STL file

- added an option to the GEO output routine to save the surface mesh
  as discrete surfaces associated with the geometrical surfaces

- added STL and Text output formats for post-processing views (the
  text output allows for example to exploit plugin-generated data in
  gnuplot)

- generalized Plugin(Evaluate):

  * can loop automatically over all the timestep and/or components

  * can do operations using data from an external view

     - if the 2 views are based on the same grid, the plugin does the
       evaluation very efficiently

     - if the 2 views are based on differenet grids, the plugin
       automatically interpolates the external view data onto the
       grid of the current view

- added new Rand() function in MathEval

- default colormap is now # 2 (the Matlab "Jet" colormap)

new "Remove->Other Views" menu

group the 2 anim demos in a single, interactive one

Generalized the Levelset routines so that we can compute isovolumes with
all levelset-based plugins. This allows to extract either side of a
levelset (i.e., a half space with CutPlane, the interior/exterior of
a sphere with CutSphere, or the isovolume inside an isosurface with
CutMap).

add option to specify the size of the small axes

use v0, v1, ..., vn to access the other components of the field

add special token "Today" to return the current date

"make purge" should also remove .#* files

fix small mistake in definition of char-expression

copyright update

- More intelligent way to detect if we need to apply a polygon offset
or not.

- better computation of translation coef in Draw2D

remove extra test on !port

better handling of end-of-string characters in text strings (which removes
the need for the ugly '^' hack) -> bumped file format version from 1.2 to 1.3

The TCP patch broke UNIX solckets on Winwows (since Windows paths can
contain a colon)

the TCP patch broke UNIX sockets on Windows (since Windows paths already
contain a colon)

sanitize TeX strings in an "intelligent" way

Added 2 options to control polygon offset. Instead of trying to guess
when a polygon offset is useful (it's no that simple when we combine
geo+mesh+some views), we just apply it conditionally to all surface
drawings.

optimize ExportLc

test if there is anything to save before opening the file

generalized ExportLcField to all element types

fixed computation of Min/Max when the view contains different element types

pretty print messages and comments

Ctrl+a->Shift+a

Replaced all *non-modal* Fl_Windows with either Dialog_Windows or
Main_Windows, which are derived from Fl_Window amd correctly process
the OS-specific "Close Window" shortcuts (Pomme+W on MacOS, Alt+F4 on
Win32).

Opengl_Window should not take the keyboard focus by force as soon the
mouse enters its area (this messes up the processing of other windows
shortcuts). Instead, it should only force the focus when it gets a
mouse click. This is much nicer.

prevent crash when no contour

Small aesthetic changes:

- Only 'title-capitalize' window titles and menus; the rest should be
  capitalized like normal english sentences

- The window title should be exactly the same as the menu item
  (without the ellipsis character if there is one)

Print "Shift+Ctrl" instead of "Ctrl+Shift" in the docs, since this is the
way both FLTK and MacOS do it

show 'About' window in the middle of the screen

final shortcut changes decided by Laurent

- On Mac, Cmd==Ctrl
- better menu dividers

- reworked the keyboard shortcuts with Laurent (our very own Macintosh
  Usability Guidelines Expert)

- new smoothing option for jpeg output

- new small GUI dialogs for ps/pdf/jpeg/gif/msh output (makes the
  'format' menu in the file dialog much shorter)