func getId(r *http.Request) int {
	id, err := strconv.Atoi(mux.Vars(r)["id"])
	// This will return a 500 instead of 404 because we have parameter
	// validation in routes.go that only allows numbers for id.  If there
	// is an error here, it is something different and most likely a 500.
	util.CheckErr(err)
	return id
}
func getFormInt(fieldName string, r *http.Request) int {
	// TODO this error handling will probably need to be different.
	i, err := strconv.Atoi(r.PostForm.Get(fieldName))
	util.CheckErr(err)
	return i
}