Add mailnode's ip to dns templates

As a System Administrator, I would like to be able to use variables for mailnode hostnames in zone templates to avoid using cnames in custom templates.

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According to current docs:

https://docs.cpanel.net/whm/dns-functions/edit-zone-templates/

%maildomain% — The hostname of the server that handles the domain’s mail.

When you link a box with a mailnode, this variable stores the mailnode's hostname. It would be very useful to have a variable like %mailip% to store the ip of the mailnode.

For example, to avoid cnames in custom templates.

Thanks.