add remarck on mixed struct+unstruct vol meshes with old iso 3d algo

set char length from lines (useful if we want to mesh 2D from boundary repres)

cannot init iterator with 0: breaks on gcc 4.1

minimize the number of files that include GmshVersion.h: it's annoying to
recompiletoo many files just because the version string changes

new plugin to extract the geometry edges

add a couple more safeguards in ReceiveXX routines

redhat->rpm

TODO->doc

I won't build rpms by default anymore

fix fpe

typo

fix popup+make depend

fix left popup

truunk will be 2.0 eventually

Workaround for FLTK 1.1.7 popup menu bug (which could cause gmsh to
crash when deleting a post-pro view).

Since we are going to make a LOT of changes in the geometry module in the
near future, I am going to create a branch with 1.64, which will be the
last "1.XX" version. I'll try to release 1.64 as soon as possible. Only
small bug fixes will go into that branch.

The trunk will get all the modeler changes, and will eventually become
Gmsh 2.0.

run autoconf on JF's changes

add warning about fltk 1.1.7

fix cygwin compile

rewrite

moved most OS-dependent functions in OS.cpp