Response on registration or authorization error does not come to the promise

[trean]

Response on registration or authorization error does not come to the promise

For example if a wrong email has been sent in request:

mongoSitesApi
    .auth(email, passwd)
    .then(function (res) {

      // nothing here

    }, function (err) {

      // nothing here

    })
    .catch(function (err) {
     
     // error was catched but error is undefined

    });

[DefeNder93]

see PR #7