[glibmm] Link to a bug report

[Murray Cumming <murrayc src gnome org>]

commit d43948051e71ef5d8b87e480c0028f90e60a591a
Author: Murray Cumming <murrayc murrayc com>
Date:   Fri Aug 9 11:58:45 2013 +0200

    Link to a bug report

 gio/src/simpleactiongroup.hg |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/gio/src/simpleactiongroup.hg b/gio/src/simpleactiongroup.hg
index 9055877..9c72891 100644
--- a/gio/src/simpleactiongroup.hg
+++ b/gio/src/simpleactiongroup.hg
@@ -47,6 +47,8 @@ public:
   _WRAP_METHOD_DOCS_ONLY(g_simple_action_group_new)
   _WRAP_CREATE()
 
+  //See bug #https://bugzilla.gnome.org/show_bug.cgi?id=705600 about deprecating these functions in the C 
API.
+
   _WRAP_METHOD(Glib::RefPtr<Action> lookup(const Glib::ustring& action_name), g_simple_action_group_lookup, 
refreturn, deprecated "Use ActionMap::lookup_action() instead")
   _WRAP_METHOD(Glib::RefPtr<const Action> lookup(const Glib::ustring& action_name) const, 
g_simple_action_group_lookup, refreturn, constversion, deprecated "Use ActionMap::lookup_action() instead")