[glibmm] Glib::init(), Gio::init(): Improve the documentation

[Kjell Ahlstedt <kjellahl src gnome org>]

commit b82a639c24b0419f1cf8ad6a112d20dfed3d00df
Author: Kjell Ahlstedt <kjellahlstedt gmail com>
Date:   Tue Jul 9 16:24:55 2019 +0200

    Glib::init(), Gio::init(): Improve the documentation
    
    See issue #49

 gio/giomm/init.h   | 11 ++++++++++-
 glib/glibmm/init.h | 10 ++++++----
 2 files changed, 16 insertions(+), 5 deletions(-)
---
diff --git a/gio/giomm/init.h b/gio/giomm/init.h
index 345e8194..0dd3c882 100644
--- a/gio/giomm/init.h
+++ b/gio/giomm/init.h
@@ -24,7 +24,16 @@
 namespace Gio
 {
 
-/** Initialize giomm.
+/** Initialize giomm and glibmm.
+ *
+ * Call it before you use other parts of giomm. You may call it more than once.
+ * Calls after the first one have no effect. %Gio::init() calls Glib::init(), which
+ * sets the global locale as specified by Glib::set_init_to_users_preferred_locale().
+ *
+ * You do not need to call %Gio::init() if you are using Gtk::Application,
+ * because it calls %Gio::init() for you.
+ *
+ * @see Glib::set_init_to_users_preferred_locale()
  */
 void init();
 
diff --git a/glib/glibmm/init.h b/glib/glibmm/init.h
index f93d9d59..f41040af 100644
--- a/glib/glibmm/init.h
+++ b/glib/glibmm/init.h
@@ -22,10 +22,12 @@ namespace Glib
 
 /** Initialize glibmm.
  *
- * You may call this more than once. Calls after the first one have no effect.
- * Sets the global locale as specified by set_init_to_users_preferred_locale().
- * You do not need to call %Glib::init() if you are using Gtk::Application,
- * because it calls %Glib::init() for you.
+ * Call it before you use other parts of glibmm. You may call it more than once.
+ * Calls after the first one have no effect. %Glib::init() sets the global locale
+ * as specified by set_init_to_users_preferred_locale().
+ *
+ * You do not need to call %Glib::init() if you are using Gtk::Application or
+ * Gio::init(), because they call %Glib::init() for you.
  *
  * @see set_init_to_users_preferred_locale()
  */