started to create parallel topology in the mesh

- pretty print code

never ever change the immutable vertex numbers: otherwise we cannot use
our algorithms from outside with prescribed boundary meshes

-> use MVertex::_index instead

(renamed setNum to forceNum to make sure we don't use setNum by mistake)

enhence statreport

fix crash in remeshUnrecoveredEdges

remove "return" added in orientMeshGFace in revision 1.183

this fixes the surface mesh orientation problem (wrong in 2.4.0)

fix crash in remeshUnrecoveredEdges

fix cl comp pb for embedded verts

rewrote gmsh2DMeshGenerator to make it thread-safe

*** PLEASE TEST THAT THE 2D MESH GENERATORS BEHAVE EXACTLY AS BEFORE ***

fix warnings

remove last statics to make BDS thread-safe

make divide & conquer thread-safe by encapsulating everything into the DocRecord class

oops, should not have committed openmp tests with jf

add benchmark/boolean

re-committing work from last two days after server crash:

- refactored old Geo code (new/delete)
- moved DrawPlugin to Plugin
- move from matheval to mathex
- move from Flu_Tree_Browser to Fl_Tree
- fixed crash in Triangulate plugin

- moved GUI to FlGui + added experimental QGui to test Qt

- fixed most MSVC and gcc compiler warnings

- converted some remaining tabs to whitespace (that's why the patch is
  so large; please try to remember to indent with 2 spaces and not
  tabs when you commit stuff to CVS)

- merged modified patch from Konstantinos Poulios to allow saving
  physical/partition as element tags in mesh formats that don't
  support them natively