untabify

api cleanup: use ByTag consistently (emphasises slowness of lookup)

- clean up GModel API (xxByTag -> getXx, numXx -> getNumXxes, ...)

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

fix infinite loop

fix some of the demos + clarify some comments

cleanup previous commit + move "carve hole" routines in separate file

Temporary fix for 'could not find extruded vertex' bug.

This is a serious bug, which is related to the way we use std::set to
search for points: cf. benchmark/bug/test_problem_point_set_search.cpp

THIS PROBLEM IS ALSO PRESENT IN BDS. WE NEED TO FIND A BETTER FIX!

enable new Delaunay for plane surfaces

experimental: don't use it for now

- preliminary work to interface more parser functions with general
  GEntities

- we can now export simple GModels as.geo files (points, straight line
  segments, plane surfaces, ruled surfaces and volumes are treated
  correctly; all non-straight-line curves are exported as splines; all
  non-plane/ruled surfaces are not exported)

- tentative fix for the unv export problem reported on the mailing
  list (fprintf() buggy on some machines??)

- new IO (both read and write) for structured grids using the NASA
  Plot3D format (for Olivier)

new boundary layer mesh generator

refactored smooth value/smooth normal code into single SmoothData.* file

- fixed missing return value in OCCVertex::reparamOnFace

- added code to highlight orphan entities (dave's idea)

- added gui for incomplete second order elements

- removed ugly static variables in 1d algo

- made sure we remove all 2d order vertices before generating new ones

- reimplemented subdivision of extruded meshes
- fix indent + unused var + gcc warnings all over the place

print warning for now when extrusion mesh is not recombined

better tol in extrude

- finished volume extrusion
- cleanup ExtrudeParam (plug memory leak + remove unused stuff)
- make netgen the default 3D algo for now (since it actually works)

remove more attractor crap

fine tuning

fix off-by-one bug in the computation of u

extrude edge+face (only "recombined" for now; we'll implement subdivision
into simplices "globally" later)

start work on extrusion

don't build metis and ann by default anymore

some initial steps before reimplemeting extrusion