Add context to banner button text

Needs flash messaging system changes.

app/templates/flash_messages.html

@@ -15,7 +15,8 @@
           'default' if ((category == 'default') or (category == 'default_with_tick')) else 'dangerous',
           delete_button=delete_button_text,
           with_tick=True if category == 'default_with_tick' else False,
-          context=message[1] if message is not string
+          context=message[1] if message is not string,
+          thing=message[2] if message is not string and message[2]
         )}}
       </div>
     {% endfor %}