code: public HttpRequest basicAuth(String username, String password) {
  		final String data = username.concat(":").concat(password);
  		final String base64 = Base64.encode(data, charset);
  
  		header("Authorization", "Basic " + base64, true);
  
  		return this;
  	}
docs: 简单验证
  
  @param username 用户名
  @param password 密码
  @return HttpRequest