Add an option that allows me to fully disable email hosting

As a cPanel Systems Administrator, I would like to fully disable email hosting, and related settings, so that server resources are not wasted, users are not confused by extraneous options, and troubleshooting errors will not be complicated by unused email related settings.

This would also ensure that any email related security issues cannot effect installs that do not use email.

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At my workplace, all email is handled outside of cPanel. We will never need to host email on the cPanel server. As such, the email daemon's, subdomains, etc. simply provide no benefit. I would like to be able to disable them entirely. As in the OS packages would not be installed, the daemons would not run, and there would be no email hosting related configuration options anywhere in WHM or cPanel.

I believe this could also help cPanel run better. It would not be able to expect an email hosting related service to exists and then run into errors when that service does not function correctly.