supervisor list improvement

sails/src/assets/scripts/modules/supervisor/views/supervisors_list.html

@@ -60,8 +60,8 @@
               <div class="col-xs-9">
                 <h4>{{supervisor.name}} {{supervisor.surname}}</h4>
                 <p><span class="text-muted">{{ supervisor.role | translate }}</span></p>
-                <p><i class="fa fa-envelope" aria-hidden="true" ng-if="{{supervisor.email}}"></i><a href="mailto:{{supervisor.email}}" ng-if="{{supervisor.email}}"> {{supervisor.email}}</a></p>
-                <p><i class="fa fa-phone-square" aria-hidden="true" ng-if="{{supervisor.phone}}"></i><a href="tel:{{supervisor.phone}}" ng-if="{{supervisor.phone}}"> {{supervisor.phone}}</a></p>
+                <p><i class="fa fa-envelope" aria-hidden="true" ng-if="supervisor.email != null"></i><a href="mailto:{{supervisor.email}}" ng-if="supervisor.email != null"> {{supervisor.email}}</a></p>
+                <p><i class="fa fa-phone-square" aria-hidden="true" ng-if="supervisor.phone != null"></i><a href="tel:{{supervisor.phone}}" ng-if="supervisor.phone != null"> {{supervisor.phone}}</a></p>
               </div>
             </div>
           </td>