def set_http_service(domain = nil, username = nil, password = nil)
      self.domain    = domain
      self.user_name = username
      self.password  = password
      self.service   = Credential::Service::HTTP
    end
def set_http_service(domain = nil, username = nil, password = nil)
      self.domain    = domain
      self.user_name = username
      self.password  = password
      self.service   = Credential::Service::HTTP
    end
sets the Web Site HTTP Authentication service.