Add footer section to email indicating this is an automated message

src/main/resources/templates/emails/form_membership_email_template.txt

@@ -47,3 +47,8 @@ Effective Date: {wg.effectiveDate}
 Contact Name: {wg.contact.fName} {wg.contact.lName}
 
 {/for}
+
+----------
+
+This is an automatic message from https://membership.eclipse.org
+Twitter: @EclipseFdn

src/main/resources/templates/emails/form_membership_email_web_template.html

@@ -69,6 +69,9 @@
           {/for}
         </tbody>
       </table>
+      <hr style="margin:40px 20px ">
+      <p style="text-align: center">This is an automatic message from <a href="https://membership.eclipse.org">https://membership.eclipse.org</a></p>
+      <p style="text-align: center">Twitter: <a href="https://twitter.com/EclipseFdn">@EclipseFdn</a></p>
     </div>
   </div>
 </div>