Fixed typo

Author: Nyholm

README.md

@@ -35,7 +35,7 @@ $ php composer.phar require knplabs/github-api php-http/guzzle6-adapter
 
 > `php-github-api` follows the PSR-4 convention names for its classes, which means you can easily integrate `php-github-api` classes loading in your own autoloader.
 
-Why `php-http/guzzle6-adapter`? We are decoupled form any HTTP messaging client with help by [HTTPlug](http://httplug.io/). Read about clients in our [docs](doc/cusomize.md).
+Why `php-http/guzzle6-adapter`? We are decoupled form any HTTP messaging client with help by [HTTPlug](http://httplug.io/). Read about clients in our [docs](doc/customize.md).
 
 ## Using Laravel?