title: How to set HTTP Request Header "authentication" using HTTPClient?
body: <p>I want to set the HTTP Request header "Authorization" when sending a POST request to a server.
  How do I do it in Java? Does HttpClient have any support for it?</p>
  
  <p><a href="http://www.w3.org/Protocols/HTTP/HTRQ_Headers.html#z9" rel="noreferrer">http://www.w3.org/Protocols/HTTP/HTRQ_Headers.html#z9</a></p>
  
  <p>The server requires me to set some specific value for the authorization field:
  of the form ID:signature which they will then use to authenticate the request.</p>
  
  <p>Thanks
  Ajay</p>