Unify examples structure (#1118)

* Animations, CameraAndViewport, CollisionDetection and Components unified

* Added descriptions to effects

* Rename input games

* Unify input stories

* Add info to parallax section

* Added descriptions to the rendering examples

* Add descriptions to the sprites directory

* Fix utils and rendering section

* Add descriptions to the widgets section

* Delete directory that rebase brought back

* Unify game names

* Added some styleguide docs for examples

* Fix analyze issues

* All files should have _example as suffix

* Made the FollowComponentExample a bit easier to understand

* Change priority of ember

examples/lib/stories/input/mouse_movement_example.dart

@@ -0,0 +1,53 @@
+import 'package:flame/extensions.dart';
+import 'package:flame/game.dart';
+import 'package:flame/input.dart';
+import 'package:flame/palette.dart';
+import 'package:flutter/material.dart';
+
+class MouseMovementExample extends FlameGame with MouseMovementDetector {
+  static const String description = '''
+    In this example we show how you can use `MouseMovementDetector`.\n\n
+    Move around the mouse on the canvas and the white square will follow it and
+    turn into blue if it reaches the mouse, or the edge of the canvas.
+  ''';
+
+  static const speed = 200;
+  static final Paint _blue = BasicPalette.blue.paint();
+  static final Paint _white = BasicPalette.white.paint();
+  static final Vector2 objSize = Vector2.all(50);
+
+  Vector2 position = Vector2(0, 0);
+  Vector2? target;
+
+  bool onTarget = false;
+
+  @override
+  void onMouseMove(PointerHoverInfo info) {
+    target = info.eventPosition.game;
+  }
+
+  Rect _toRect() => position.toPositionedRect(objSize);
+
+  @override
+  void render(Canvas canvas) {
+    super.render(canvas);
+    canvas.drawRect(
+      _toRect(),
+      onTarget ? _blue : _white,
+    );
+  }
+
+  @override
+  void update(double dt) {
+    final target = this.target;
+    super.update(dt);
+    if (target != null) {
+      onTarget = _toRect().contains(target.toOffset());
+
+      if (!onTarget) {
+        final dir = (target - position).normalized();
+        position += dir * (speed * dt);
+      }
+    }
+  }
+}