Added documentation

Author: damianopetrungaro

README.md

@@ -1,6 +1,40 @@
 # Moon - HTTP Middleware
 A very simple HTTP Middleware implementation
 
-[![Code Climate](https://codeclimate.com/github/moon-php/logger/badges/gpa.svg)](https://codeclimate.com/github/moon-php/http-middleware) [![Build Status](https://travis-ci.org/moon-php/logger.svg?branch=master)](https://travis-ci.org/moon-php/http-middleware)
+[![Scrutinizer Code Quality](https://scrutinizer-ci.com/g/moon-php/http-middleware/badges/quality-score.png?b=master)](https://scrutinizer-ci.com/g/moon-php/http-middleware/?branch=master)
+[![Code Coverage](https://scrutinizer-ci.com/g/moon-php/http-middleware/badges/coverage.png?b=master)](https://scrutinizer-ci.com/g/moon-php/http-middleware/?branch=master)
+[![Build Status](https://scrutinizer-ci.com/g/moon-php/http-middleware/badges/build.png?b=master)](https://scrutinizer-ci.com/g/moon-php/http-middleware/build-status/master)
 
-## In Development
+## Documentation
+
+- Delegate
+
+- InvalidArgumentException
+
+
+
+### Delegate
+
+__namespace: Moon\HttpMiddleware\Delegate__
+
+According to the PSR15 proposal : 
+
+_The DelegateInterface defines a single method that accepts a request and returns a response._
+
+_The delegate interface must be implemented by any middleware dispatcher that uses middleware implementing MiddlewareInterface._
+
+So i decided to make the **Delegate** a **Middleware Dispatcher** itself.
+
+The object is really simple, it has a constructor that requires an **array of MiddlewareInterface** implementor and a callable to use as **default** response.
+
+The MiddlewareInterface implementor will be directly implemented by the userland and inserted into the array.
+
+    $request = new ServerRequestImplementor();
+    $delegate = new Delegate([new MiddlewareOne(), new MiddlewareTwo(), new MiddlewareThree()], new DefaultResponse());
+    $delegate->process($request);
+
+### InvalidArgumentException
+
+__namespace Moon\HttpMiddleware\Exception\InvalidArgumentException__
+
+If an object passed into the array is not a MiddlewareInterface implementor and **InvalidArgumentException** will be thrown.