rename benutzer to users

add role management to media page

dashboard/src/App.tsx

@@ -44,7 +44,7 @@ import Ressourcen from './ressourcen';
 import Infoscreens from './clients';
 import Infoscreen_groups from './infoscreen_groups';
 import Media from './media';
-import Benutzer from './benutzer';
+import Benutzer from './users';
 import Einstellungen from './settings';
 import SetupMode from './SetupMode';
 import Programminfo from './programminfo';