added sent and id column again for add_cam_main

id checks if entry already exists. sent says if the entry is already
sent to the db

lib/screens/excursion/excursion_main.dart

@@ -360,6 +360,7 @@ class _ExcursionMainState extends State<ExcursionMain> {
                   context,
                   getFieldsText(),
                   false,
+                  DatabasesEnum.excursion
                 );
               }
             }