FIX: rmpty text for group an oe list

frontend/src/components/GroupCard.vue

@@ -170,6 +170,10 @@
                      variant="success" placement="bottom">
             Neue Untergruppe anlegen
           </b-tooltip>
+          <div v-if="!subgroups || subgroups.length === 0"
+               class="font-italic text-center mb-3">
+            Keine Untergruppen vorhanden
+          </div>
           <GroupCard v-for="sub in subgroups" v-bind:key="sub.name"
                      :group="sub"
                      :groups="groups"

frontend/src/views/cntl/Groups.vue

@@ -36,6 +36,10 @@
         >
         </GroupCard>
       </template>
+      <div v-if="!groups || groups.length === 0"
+           class="font-italic text-center mb-3">
+        Keine Gruppen vorhanden
+      </div>
     </Loading>
     <DBEditor modal_id="assign_to_group" :object_function="db_editor_function"
               :object_fq_name="db_editor_object_fq_name"

frontend/src/views/cntl/OU.vue

@@ -48,6 +48,10 @@
           </b-collapse>
         </b-card>
       </template>
+      <div v-if="!ous || ous.length === 0"
+           class="font-italic text-center mb-3">
+        Keine Organisationseinheiten vorhanden
+      </div>
     </Loading>
     <DBEditor modal_id="assign_user_to_oe" object_function="create" object_fq_name="cntl.mgr2ou" :presets="db_editor_presets"
     :non_optionals_order="['ou_short_name', 'mgr_login_name']" object_title="Konto-zu-Organisationseinheits-Zuordnung"></DBEditor>