Added class groups example to Doxygen and added parent "Functions and Macros", and "Classes by Category" groups.

Also added CSS to add "Categories / " to the "Modules" tab label, and turned on DETAILS_AT_TOP setting.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@52454 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

interface/gdicmn.h

@@ -326,6 +326,7 @@ public:
 
 /**
     @class wxBrushList
+    @ingroup group_class_gdi
     @wxheader{gdicmn.h}
 
     A brush list is a list containing all brushes which have been created.
@@ -476,6 +477,7 @@ public:
 
 /**
     @class wxFontList
+    @ingroup group_class_gdi
     @wxheader{gdicmn.h}
 
     A font list is a list containing all fonts which have been created. There
@@ -668,6 +670,7 @@ public:
 
 /**
     @class wxPenList
+    @ingroup group_class_gdi
     @wxheader{gdicmn.h}
 
     There is only one instance of this class: @b wxThePenList.  Use
@@ -739,7 +742,7 @@ public:
 // Global functions/macros
 // ============================================================================
 
-/** @addtogroup group_gdi */
+/** @ingroup group_funcmacro_gdi */
 //@{
 
 /**