updating README and fixing typo

Add PHP version to readme.md's requirements

README.md

@@ -22,6 +22,7 @@ Unirest is a set of lightweight HTTP libraries available in [multiple languages]
 ## Requirements
 
 - [cURL](http://php.net/manual/en/book.curl.php)
+- PHP 5.4+
 
 ## Installation
 
@@ -156,6 +157,16 @@ $response = Unirest\Request::get("http://mockbin.com/request", null, null, "user
 
 **This has been deprecated, and will be completely removed in `v.3.0.0` please use the `Unirest\Request::auth()` method instead**
 
+### Cookies
+
+Set a cookie file path for enabling cookie reading and storing cookies across multiple sequence of requests.
+
+```php
+Unirest\Request::cookieFile($cookieFile)
+```
+
+`$cookieFile` must be a correct path with write permission.
+
 ### Request Object
 
 ```php

src/Unirest/Request.php

@@ -7,11 +7,12 @@ use Unirest\Response;
 
 class Request
 {
+    private static $cookieFile = null;
+    private static $defaultHeaders = array();
     private static $handle = null;
     private static $jsonOpts = array();
-    private static $verifyPeer = true;
     private static $socketTimeout = null;
-    private static $defaultHeaders = array();
+    private static $verifyPeer = true;
 
     private static $auth = array (
         'user' => '',
@@ -102,6 +103,18 @@ class Request
         return self::defaultHeader('X-Mashape-Key', $key);
     }
 
+    /**
+     * Set a coockie file path for enabling coockie handling
+     *
+     * $cookieFile must be a correct path with write permission
+     *
+     * @param string $cookieFile - path to file for saving cookie
+     */
+    public static function cookieFile($cookieFile)
+    {
+        self::$cookieFile = $cookieFile;
+    }
+
     /**
      * Clear all the default headers
      */
@@ -360,6 +373,11 @@ class Request
             curl_setopt(self::$handle, CURLOPT_TIMEOUT, self::$socketTimeout);
         }
 
+        if (self::$cookieFile) {
+            curl_setopt($ch, CURLOPT_COOKIEFILE, self::$cookieFile);
+            curl_setopt($ch, CURLOPT_COOKIEJAR, self::$cookieFile);
+        }
+
         // supporting deprecated http auth method
         if (!empty($username)) {
             curl_setopt_array(self::$handle, array(