Update labels in nuxeoctl to mention tokens instead of password

In order to know that a token is needed to execute a command against nos after migrating to okta

AC
when using a command that requires a password like nuxeoctl register, label is changed from

Please enter your password:

to

Please enter your token:

When entering a wrong login / token couple, answer is changed from:

Unhandled response code: 401
Wrong login or password.

to:

Wrong login or token. Please make sure you use a token created at https://connect.nuxeo.com/nuxeo/site/connect/tokens