Automatically generate mandatory email addresses on domain creation

[martbock]

Since some email addresses are required to be always present for every domain, it would be cool to have an option that - when enabled - automatically generates those addresses once a new domain is added.

Mandatory email addresses are

• abuse@
• postmaster@

Other useful ones could be

• hostmaster@
• webmaster@

One step further would be to allow for custom addresses that are generated on every domain creation.

Probably the easiest thing we could do is hook some kind of EventListener onto a domain creation event and have a boolean in the .env file to enable/disable the function. Another possibility would be to have a setting saved in the database.