Docs: Add "usage" section to readme

README.md

@@ -2,3 +2,21 @@ sparkles
 ========
 
 Namespaced global event emitter
+
+## Usage
+
+It just exports an `EventEmitter`. Think of it as a singleton.
+
+```js
+var sparkles = require('sparkles');
+
+sparkles.on('my-event', function(evt){
+  console.log('my-event handled', evt);
+});
+
+sparkles.emit('my-event', { my: 'event' });
+```
+
+## License
+
+MIT