caddyhttp: Move HTTP redirect listener to an optional module

[francislavoie]

Followup to #4313

Turns out we have some issues with this being turned on by default, so we'll have to provide it as an optional module for now.

To turn it on, this needs to be added in global options:

{
	servers {
		listener_wrappers {
			http_redirect
			tls
		}
	}
}

[mholt]

Thanks Francis, this should do the trick. Looks good! Just a nit on the naming.

[mholt]

Awesome, thanks Francis!