code: function createCustomLabel (name) {
    return new Promise (async (resolve, reject) => {
      if (!name) {
        reject('name required');
      }
      let options = {
        'payload': {'name': name}
      };
      try {
        let response = await  this.callCustomLabelsApi(options);
        resolve(response);
      } catch (e) {
        reject(e);
      }
    });
  }
docs: Creates a new custom label.
  @param  {String}  name  The name of the custom label.
  @return {Promise<Object>}  The API response
  @memberof  Client#
  @example
  Client.createCustomLabel('my_custom_label')
  .then(res => {
  console.log(res); // {"id": "9485676932424"}
  });