Fix certification from small screen

www/templates/wot/view_identity.html

@@ -63,7 +63,7 @@
   </button>
 
   <button class="button button-fab button-fab-bottom-right button-assertive icon ion-ribbon-b visible-xs visible-sm"
-          ng-click="signIdentity()"
+          ng-click="certifyIdentity()"
           ng-if="hasSelf"
           style="bottom:78px;">
   </button>