Readme: add Installation notes

Author: TooTallNate

Readme.md

@@ -3,6 +3,20 @@
 
 A simple JSONP implementation.
 
+## Installation
+
+Install for node.js or browserify using `npm`:
+
+``` bash
+$ npm install jsonp
+```
+
+Install for component(1) using `component`:
+
+``` bash
+$ component install LearnBoost/jsonp
+```
+
 ## API
 
 ### jsonp(url, opts, fn)