* classify and sort the doxygen "related pages"

  by tweaking the filename and adding 2 categories:
   Troubleshooting and Advanced
* use the EXCLUDE_SYMBOLS to clean the class list
  (insteaded of a homemade bash script)
* remove the broken "exemple list"
* re-structure the unsupported directory as mentionned in the ML and
  integrate the doc as follow:
  - snippets of the unsupported directory are directly imported from the
    main snippets/CMakefile.txt (no need to duplicate code)
  - add a top level "Unsupported modules" group
  - unsupported modules have to defined their own sub group and nest it
    using \ingroup Unsupported_modules
  - then a pair of //@{ //@} will put everything in the submodule
  - this is just a proposal !

1 files changed, 15 insertions, 0 deletions

diff --git a/unsupported/doc/unsupported.dox b/unsupported/doc/unsupported.dox
new file mode 100644
index 000000000..abef263ad
--- /dev/null
+++ b/unsupported/doc/unsupported.dox
@@ -0,0 +1,15 @@
+
+namespace Eigen {
+
+namespace unsupported {
+
+/** \defgroup Unsupported_modules Unsupported modules
+  *
+  * The unsupported modules are contributions from various users. They are
+  * provided "as is", without any support. Nevertheless, they are subject to be
+  * included in Eigen in the future.
+  */
+
+} // namespace unsupported
+
+} // namespace Eigen
\ No newline at end of file