client.go
func GetDeadline(dst []byte, url string, deadline time.Time) (statusCode int, body []byte, err error) {
	return defaultClient.GetDeadline(dst, url, deadline)
}
func GetDeadline(dst []byte, url string, deadline time.Time) (statusCode int, body []byte, err error) {
	return defaultClient.GetDeadline(dst, url, deadline)
}
// GetDeadline returns the status code and body of url.
//
// The contents of dst will be replaced by the body and returned, if the dst
// is too small a new slice will be allocated.
//
// The function follows redirects. Use Do* for manually handling redirects.
//
// ErrTimeout error is returned if url contents couldn't be fetched
// until the given deadline.