PLT-2971 Added email footer for address (#3319)

* Added email footer for address

* added default

* Update html.go

* Changed according to PM

templates/email_footer.html

@@ -2,7 +2,7 @@
 
 <td style="text-align: center;color: #AAA; font-size: 11px; padding-bottom: 10px;">
     <p style="padding: 0 50px;">
-        (c) 2015 Mattermost, Inc. 855 El Camino Real, 13A-168, Palo Alto, CA, 94301.<br>
+        {{.Props.Organization}}<br>
         {{.Props.Footer}}
     </p>
 </td>