touch ./animations (#148)

* Update project structure using flutter create and remove unused tests
* Small updates to main.dart
* Update maintenance.md
* Add missing newline
* Add rudimentary test
* Apply formatting

animations/test/empty_test.dart

@@ -1,9 +0,0 @@
-// Copyright 2019 The Flutter team. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-import 'package:flutter_test/flutter_test.dart';
-
-void main() {
-  testWidgets('This test always passes', (tester) async {});
-}

animations/test/widget_test.dart

@@ -0,0 +1,20 @@
+// This is a basic Flutter widget test.
+//
+// To perform an interaction with a widget in your test, use the WidgetTester
+// utility that Flutter provides. For example, you can send tap and scroll
+// gestures. You can also use WidgetTester to find child widgets in the widget
+// tree, read text, and verify that the values of widget properties are correct.
+
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:animations/main.dart';
+
+void main() {
+  testWidgets('Counter increments smoke test', (tester) async {
+    // Build our app and trigger a frame.
+    await tester.pumpWidget(AnimationSamples());
+
+    // Verify that a least one of our demos is showing up in the list
+    expect(find.text('AnimatedContainer'), findsOneWidget);
+  });
+}