Deletion of accounts that were not activated

[vtomberg]

After two months delay accounts, which never have been activated should be deleted automatically.

[pjotrsavitski]

This should be easily done by choosing a cron/periodic job module (any one that seems to be maintained to would with new Node.js versions and has enough usage).

Later on a job could either be registered with starting the backend service or a standalone script could be used for that. It does not really have to have much insight into the logic of the system, just to have the database connection and ability to run a simple query that would purge any accounts that fit certain condition (the connection could even be established each time that job starts and terminated as soon as it finishes).

The standalone solution seems to be better as it would not cause issues in case of running multiple instances as a cluster.