func Hello(w http.ResponseWriter, r *http.Request, ps httprouter.Params) {
  log.Println("Hello Controller")
  fmt.Fprintf(w, models.Hello())
}
func Hello(w http.ResponseWriter, req *http.Request) {
  log.Println("Hello Controller")
  io.WriteString(w, models.Hello())
}
func Hello(c *echo.Context) error {
  log.Println("Hello Controller")
  return c.String(http.StatusOK, models.Hello())
}