[iagno] Add a shortcut.

[Arnaud B. <arnaudb src gnome org>]

commit 4db60176d9fc646b56774bfd55d989d843179924
Author: Arnaud Bonatti <arnaud bonatti gmail com>
Date:   Wed Jul 31 11:50:56 2019 +0200

    Add a shortcut.
    
    Allow Shift-Primary-q
    for closing the game.

 src/iagno.vala | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
---
diff --git a/src/iagno.vala b/src/iagno.vala
index 93ef8e2..4e0b786 100644
--- a/src/iagno.vala
+++ b/src/iagno.vala
@@ -306,7 +306,8 @@ private class Iagno : Gtk.Application
         add_action_entries (app_actions, this);
         set_accels_for_action ("ui.new-game",           {        "<Primary>n"       });
         set_accels_for_action ("ui.start-game",         { "<Shift><Primary>n"       });
-        set_accels_for_action ("app.quit",              {        "<Primary>q"       });
+        set_accels_for_action ("app.quit",              {        "<Primary>q",
+                                                          "<Shift><Primary>q"       });
         set_accels_for_action ("ui.undo",               {        "<Primary>z"       });
      // set_accels_for_action ("ui.redo",               { "<Shift><Primary>z"       });
         set_accels_for_action ("ui.back",               {                 "Escape"  });