added some more topological infos in high order elements (useful for DGM,
still have to be tested)

* rewrite femTerm in terms of SElement

renamed most gmsh* classes

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