This module implements a client the HTTP protocol.
Fetches the document pointed to by URL from Internet, using request parameters Request (get method by default), and unifies Response with the parameters of the response. Fails on timeout. Note that redirections are not handled automatically, that is, if Response contains terms of the form status(redirection,301,_) and location(NewURL), the program should in most cases access location NewURL.
Usage:fetch_url(URL,Request,Response)