updated readme

Author: fb55

readme.md

@@ -1,3 +1,40 @@
 #CSSwhat [![Build Status](https://secure.travis-ci.org/fb55/CSSwhat.png?branch=master)](http://travis-ci.org/fb55/CSSwhat)
 
 a CSS selector parser
+
+##Example
+
+```js
+require("CSSwhat")("foo[bar]:baz")
+
+~> [ [ { type: 'tag', name: 'foo' },
+    { type: 'attribute',
+      name: 'bar',
+      action: 'exists',
+      value: '',
+      ignoreCase: false },
+    { type: 'pseudo',
+      name: 'baz',
+      data: null } ] ]
+```
+
+##API
+
+__`CSSwhat(selector, options)` - Parses `str`, with the past `options`.__
+
+The function returns a two-dimensional array. The first array represents subselects separated by commas (eg. `sub1, sub2`), the second contains the relevant tokens for that selector. Possible token types are:
+
+name | attributes | example | output
+---- | ---------- | ------- | ------
+`tag`| `name`    | `div`   | `{ type: 'tag', name: 'div' }`
+`universal`| -   | `*`     | `{ type: 'universal' }`
+
+//TODO complete list
+
+__Options:__
+
+- `xmlMode`: When enabled, tagnames will be case-sensitive (ie. the output won't be lowercased).
+
+---
+
+License: BSD-like