code: public static Single<String> tplSendSms(String apikey, long tpl_id, String tpl_value, String mobile) {
          Map<String, String> params = new HashMap<>();
          params.put("apikey", apikey);
          params.put("tpl_id", String.valueOf(tpl_id));
          params.put("tpl_value", tpl_value);
          params.put("mobile", mobile);
          return post(URI_TPL_SEND_SMS, params);
      }
docs: 通过模板发送短信(不推荐)
  
  @param apikey    apikey
  @param tpl_id    　模板id
  @param tpl_value 　模板变量值
  @param mobile    　接受的手机号
  @return json格式字符串