Use self-signed certificate by default

[jasonish]

Create and use a self-signed certificate by default. Its become expected of network services to be a bit more secure by default.

This should be tied to requiring authentication by default.

There must be a command line option to opt out.

This crate might help to generate self signed certs programmatically: https://github.com/est31/rcgen

[jasonish]

Merged to main. EveBox will now generate a self-signed certificate and use TLS by default.