Update README.md

Add default usage

README.md

@@ -2,7 +2,7 @@
 
 A lightweight flutter package providing a miniplayer widget which resizes according to drag gestures and returns a builder function with the current height and percentage progress.
 
-## Usuage
+## Usage
 
 ```dart
 Miniplayer(
@@ -15,3 +15,47 @@ Miniplayer(
   },
 ),
 ```
+#### Default usage
+
+```
+import 'package:flutter/material.dart';
+import 'package:miniplayer/miniplayer.dart';
+
+void main() => runApp(MyApp());
+
+class MyApp extends StatelessWidget {
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      title: 'Miniplayer Demo',
+      theme: ThemeData(
+        visualDensity: VisualDensity.adaptivePlatformDensity,
+      ),
+      home: MyHomePage(),
+      builder: (context, child) { // <--- Important part
+        return Stack(
+          children: [
+            child,
+            Miniplayer(
+              minHeight: 70,
+              maxHeight: 370,
+              builder: (height, percentage) {
+                if(percentage > 0.2)
+                  //return Text('!mini');
+                else 
+                  //return Text('mini');
+              },
+            ),
+          ],
+        );
+      },
+    );
+  }
+}
+```
+
+#### Usage with BottomNavigationBar
+
+```
+Example coming soon!
+```