Update README.md and package.json.

Author: jonkemp

README.md

@@ -10,6 +10,18 @@ Install with [npm](https://npmjs.org/package/css-rules)
 npm install --save css-rules
 ```
 
+## Usage
+
+```js
+var parseCSS = require('css-rules');
+
+var rules = parseCSS(css);
+```
+
+## Credit
+
+The code for this module was originally taken from the [Juice](https://github.com/Automattic/juice) library.
+
 ## License
 
 MIT

package.json

@@ -4,7 +4,7 @@
   "description": "Returns a parse tree for a CSS source.",
   "main": "index.js",
   "scripts": {
-    "test": "'echo \"Error: no test specified\" && exit 1'"
+    "test": "echo \"Error: no test specified\" && exit 1"
   },
   "repository": {
     "type": "git",