Disable Default Admin Account

We need the ability to disable the default admin account for the Vizlib server since it does not have the ability to support MFA.  Instead of using that account, admins could just log in through Qlik Sense, which can use MFA based on the IDP leveraged.  In the event that there is a login issue using the Qlik accounts, the default admin should be able to be turned back on when logged into the server, by editing a config file or Postgres directly.  

Another option would be to make it so the vizlib server does not need to be public facing so that the login is not exposed.  all communications through Qlik would just need to be handled on the backend.