add right click menu with multiple selection and fixes

resources/history_dialog.ui

@@ -13,7 +13,7 @@
       <object class="GtkBox" id="dialog-vbox1">
         <property name="can_focus">False</property>
         <property name="orientation">vertical</property>
-        <property name="spacing">6</property>
+        <property name="spacing">12</property>
         <child internal-child="action_area">
           <object class="GtkButtonBox" id="dialog-action_area1">
             <property name="can_focus">False</property>