Integrate Nats Broadcasting for well known

The service shall integrate the cloud messageing to send broadcasts for retrieving the issuer module metadata via nats. Secondly, the service shall be able to receive new metadata when a new issuer module comes online. Each instance should connect to a postgres database to preload the settings before. The database should also contain an timestamp for last broadcast. This is only required when modus "BROADCAST" is enabled instead of "GIT".