Fixed HTTP_CLIENT_RESPONSE when dealing with redirection
   before it was storing some header in the body.
   now we added redirections: ..  which is a list of redirection informations:
     - status line
     - header
     - and eventual redirection body (but at least by default, libcurl does not cache body)

Enhanced the http_client library to be able to write directly the downloaded data into a file (or as convenient thanks to agent).