Add new flutter example of todo app with provider (#78)

todo_list_using_provider/lib/main.dart

@@ -0,0 +1,27 @@
+import 'package:flutter/material.dart';
+import 'package:provider/provider.dart';
+
+import 'notifiers/todo_list.dart';
+import 'views/home.dart';
+
+void main() {
+  runApp(MyApp());
+}
+
+class MyApp extends StatelessWidget {
+  // This widget is the root of your application.
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      title: 'Flutter Demo',
+      theme: ThemeData(
+        primarySwatch: Colors.blue,
+        visualDensity: VisualDensity.adaptivePlatformDensity,
+      ),
+      home: ChangeNotifierProvider<TodoList>(
+        create: (context) => TodoList(),
+        child: MyHomePage(title: 'Flutter Demo Home Page'),
+      ),
+    );
+  }
+}