add a centralized file to eventually hold all doxygen groups. Put a group...

add a centralized file to eventually hold all doxygen groups.  Put a group there for GeometryType and put GeometryType in it.  This fixes FlySpray issue 237

[[Imported from SVN: r4836]]

common/geometrytype.hh

@@ -16,7 +16,7 @@ namespace Dune {
      This class has to be extended if a grid implementation with new entity types
      is added to DUNE.
 
-      \ingroup GIGeometryType
+      \ingroup COGeometryType
    */
   class GeometryType
   {

common/modules

+/* This file determines the order how things appear in the doxygen
+   documentation within the dune-common module. It works like this:
+
+   @defgroup commands appear only in this file here which is
+   parsed before the other files (because it is mentioned first 
+   in the Doxyfile).
+
+   Only @addtogroup is used in the code documentation.
+*/
+
+  /**
+	 @defgroup COGeometryType GeometryType
+	 @ingroup Common
+  */

doc/doxygen/Doxyfile

@@ -452,6 +452,7 @@ WARN_LOGFILE           =
 
 INPUT                  = mainpage \
                          modules \
+                         ../../common/modules \
                          ../../common
 
 # If the value of the INPUT tag contains directories, you can use the