- 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

copyright update

This patch fixes an old design flaw in the post-processing module,
namely that we used a list of Post_View objects instead of a list of
pointers to Post_View objects in CTX.post.list.

This had many annoying consequences, in particular the fact that we
needed to be extra careful every time the list was reallocated (as
pointers to the list elements would become invalid).

I tried very hard to change the code everywhere it should be changed,
but I might have missed something. Please let me know if you see
anything suspicious (like a crash when you duplicate/remove/combine/...
post-processing views).

- the main menu is now scrollable when there are more than 25
buttons and it can handle an arbitrary number of buttons (this removes
the "100 views max in the GUI" limitation)

- the view number is now also displayed in the menu (to make it easier
to find the view when one has many many views)

- added "Remove empty views" menu item

secured most of the list_pointer accesses

Added automatic documentation generation for plugins

- better file names for views created by plugins
- use the file name as a guess for view_save_{ascii,binary}

Update copyright notice

Fixed (or added a FIXME comment) when a post.list reallocation
could lead to problems

small changes to copy the time values (instead of relying on EndView
to just add the time step number)

Make Skin a little bit more efficient by allocating/copying the values
only if the face is not found in the tree

Generalization to all kinds of elements and field types

Big Levelset rewrite (+ cleanup of all other plugins).

Not finished yet, but I need to commit this now so that I can use it
with the boss tomorrow at work.

This version should compile and have all the old features working,
plus some extras (levelsets of scalar/vector/tensor 1D, 2D and
3D simplectic views).

JF: 'Plugin(XX).Save' is now deprecated. Use 'Save View[XX] "filename"'
instead.

Reworked the help strings for all the plugins. Easier to understand,
now, Sean? :-)

Fix whitespace in copyright headers

Indented all source files using utils/gmshindent

Updated copyright