code: private Date getModificationDate(Endpoint endpoint, Date modificationDate) {
  		Date result=endpoint.lastModified();
  		if(modificationDate.after(result)) {
  			result=modificationDate;
  		}
  		return result;
  	}
docs: Enforce http://tools.ietf.org/html/rfc7232#section-2.2:
  if the clock in the request is ahead of the clock of the origin
  server (e.g., I request from Spain the update of a resource held in USA)
  the last-modified data should be changed to that of the request and not
  a generated date from the origin server