The HTTP_Client class wraps around HTTP_Request and provides a higher level
interface for performing multiple HTTP requests.

Features:
* Manages cookies and referrers between requests
* Handles HTTP redirection
* Has methods to set default headers and request parameters
* Implements the Subject-Observer design pattern: the base class sends
  events to listeners that do the response processing.

WWW: https://pear.php.net/package/HTTP_Client