Add documentation

Author: n370

README.md

@@ -0,0 +1,24 @@
+![](rollerskate.png)
+
+Yet another accordion library.
+
+```html
+<ul data-accordion>
+  <li data-accordion-item> <!-- index 0 -->
+    <div data-accordion-item-body></div>
+  <li>
+  <li data-accordion-item> <!-- index 1 and so on! -->
+    <div data-accordion-item-body></div>
+  <li>
+</ul>
+```
+
+```js
+const Rollerskate = require('rollerskate');
+const rollerskate = new Rollerskate(window);
+
+rollerskate.expandAll();
+rollerskate.collapseAll();
+rollerskate.item(0).expand();
+rollerskate.item(0).collapse();
+```