getUser () {
    return new Promise((resolve, reject) => {
      fetch('api/user').then((response) => {
        if (!response.ok) { // test for bad response code
          throw new Error(response.statusText);
        }
        return response.json();
      }).then((response) => {
        store.commit('SET_USER', response);
        return resolve(response);
      }).catch((err) => { // this catches an issue within the ^ .then
        return reject(err);
      });
    });
  }
Fetches the list of user roles.
@returns {Promise} - The promise that either resovles the request or rejects in error