Add options to run the client without rpyc autodiscovery

Rewrite periodic tasks
Update proxy config file at the right times
Implement periodic task for checking dead containers and expired notebooks

Ignore IDEA project files

Split the things in a client and a scheduler, the client will be available as a cli client or a web application.

Remove the notebooks table
Add more general proxy management
Add back links to user web pages

The database is no longer a singleton
The swarm manager is a singleton managed at package level