addUsers (id, users, cluster) {
    return new Promise((resolve, reject) => {
      const options = {
        url: `api/hunt/${id}/users`,
        method: 'POST',
        data: { users },
        params: { cluster }
      };

      Vue.axios(options).then((response) => {
        resolve(response);
      }).catch((error) => {
        reject(error);
      });
    });
  }
Adds users to a hunt
@param {string} id The id of the hunt
@param {string} users Comma separated list of users
@param {string} cluster The cluster name string of the cluster to add users to the hunt from
@returns {Promise} Promise A promise object that signals the completion
                           or rejection of the request.