cherry-pick commits to the release branch

18420a8 (Matthias Maier, 3 hours ago)
   put license.html directly on the homepage

a7941cb (Matthias Maier, 3 hours ago)
   clenaup toc, remove stale information

9f764e5 (Matthias Maier, 5 months ago)
   Documentation: remove stale html files

   Remove news.html and publications/indexl.html stubs - they are not
   referenced any more.

13082e9 (Matthias Maier, 5 months ago)
   Documentation: Remove all references to external resources

   We already link to this  external resources on the homepage - there is no
   point in doing it here (nobody will find it and it has the bad tendency of
   being out of date).

df28af5 (Matthias Maier, 5 months ago)
   Documentation: Remove svn.html from offline documentation

   The new development guidelines for git should be prominently on the
   homepage, not buried in the offlinedocumentaiton. So just remove the old
   cruft.

ac7143b (Matthias Maier, 5 months ago)
   Documentation: Remove bogus indentation.html file

   Well, we already have a detailed doxygen file about indentation. So it is
   better to add the three relevant lines about astyle there and remove this
   additional documentation page completely

7996f28 (Matthias Maier, 5 months ago)
   Documentation: Remove references to svn

   Remove references to svn's $Id$ in the headers and replace references to
   the old subversion repository in various html files

431957a (Matthias Maier, 3 hours ago)
   Fix link in step-52

6bf9424 (Timo Heister, 17 minutes ago)
   fix link to step-49 gmsh_picture.png

627151f (Martin Kronbichler, 3 hours ago)
   Fix undefined symbols on Mac.

   Deactivate ShapeInfo::reinit on MSVC target as proposed in c2021e2.

b52cd00 (Timo Heister, 16 hours ago)
   fix cmake muparser version string parsing

   Turns out there are muparser versions out there that don't have a subminor
   version which made our cmake code barf.