Implement time-range filter

flutter/lib/components/modals/filter_modal_time.dart

@@ -1,44 +0,0 @@
-import 'package:flutter/material.dart';
-import 'package:simplecloudnotifier/utils/navi.dart';
-
-class FilterModalTime extends StatefulWidget {
-  @override
-  _FilterModalTimeState createState() => _FilterModalTimeState();
-}
-
-class _FilterModalTimeState extends State<FilterModalTime> {
-  DateTime? _tsBefore = null;
-  DateTime? _tsAfter = null;
-
-  @override
-  void initState() {
-    super.initState();
-  }
-
-  @override
-  Widget build(BuildContext context) {
-    return AlertDialog(
-      title: const Text('Timerange'),
-      content: Container(
-        width: 9000,
-        height: 9000,
-        child: Placeholder(),
-      ),
-      actions: <Widget>[
-        TextButton(
-          style: TextButton.styleFrom(textStyle: Theme.of(context).textTheme.labelLarge),
-          child: const Text('Apply'),
-          onPressed: () {
-            onOkay();
-          },
-        ),
-      ],
-    );
-  }
-
-  void onOkay() {
-    Navi.popDialog(context);
-
-    //TODO
-  }
-}