Fix teacher view for no class activity

templates/teachers_show.html.tpl

@@ -106,7 +106,7 @@
 	{{range $activity := .Data.Activities}}
 	<a href="/activities/{{$activity.ID}}?{{query "tpl_layout" "base" "tpl_content" "activities_show"}}" class="list-group-item list-group-item-action">
 	  <span class="fa fa-business-time"></span>
-	  {{$activity.Subject.Name}} {{$activity.Class.Name}} {{$activity.Hours}}h{{if $activity.SupplyTeacher}}{{if ne $.Data.Surname $activity.SupplyTeacher.Surname}} (sostituito da {{$activity.SupplyTeacher.Surname}}){{else}} (sostituisce {{$activity.Teacher.Surname}}){{end}}{{end}}
+	  {{$activity.Subject.Name}} {{if $activity.Class}}{{$activity.Class.Name}}{{else}}no classe{{end}} {{$activity.Hours}}h{{if $activity.SupplyTeacher}}{{if ne $.Data.Surname $activity.SupplyTeacher.Surname}} (sostituito da {{$activity.SupplyTeacher.Surname}}){{else}} (sostituisce {{$activity.Teacher.Surname}}){{end}}{{end}}
 	  {{end}}
 	</a>
       </div>