Add option to disable or customize dashboard metrics (global / per server / per customer)

Please add an option to disable the graphs globally, per server, and/or per customer in the dashboard module.

In a multiserver setup, the metrics of the master server are always displayed, which is not the intended behavior. The metrics are very useful for customers who run their own server with a dedicated ISPConfig installation, but not when a customer has their own server that is integrated into a multiserver environment.

Additionally, the metrics are not relevant for customers hosted on a shared hosting environment.

Therefore, it should be possible to selectively enable or disable the display of metrics per customer, and ensure that the metrics shown in the customer’s dashboard are those of the server assigned to them. For example, the servers defined under Limits → Web Limits → Webserver.

This would be really important for us, since we are currently unable to use the new version in production without this functionality.