[fractal] Add the open main menu shortcut to the help dialog

[Daniel Garcia Moreno <danigm src gnome org>]

commit 505597a4b6b2b5c0b1f78f592bef1cbe13961db5
Author: João Vieira <jvieira tpt gmail com>
Date:   Sun Jun 14 11:32:17 2020 +0100

    Add the open main menu shortcut to the help dialog

 fractal-gtk/res/gtk/help-overlay.ui | 7 +++++++
 1 file changed, 7 insertions(+)
---
diff --git a/fractal-gtk/res/gtk/help-overlay.ui b/fractal-gtk/res/gtk/help-overlay.ui
index 33e44c51..9eb1061a 100644
--- a/fractal-gtk/res/gtk/help-overlay.ui
+++ b/fractal-gtk/res/gtk/help-overlay.ui
@@ -18,6 +18,13 @@
                 <property name="title" translatable="yes" context="shortcut window">Close the active 
room</property>
               </object>
             </child>
+            <child>
+              <object class="GtkShortcutsShortcut">
+                <property name="visible">true</property>
+                <property name="accelerator">F10</property>
+                <property name="title" translatable="yes" context="shortcut window">Open main menu</property>
+              </object>
+            </child>
             <child>
               <object class="GtkShortcutsShortcut">
                 <property name="visible">true</property>