Improve docs relating to email and dns functionality

It would be nice if the website had a concise _table_ of email and dns hosting capabilities and features, and a spec of functionality available in the relevant clueless UI, and also functionality in the webmail service. In the case of DNS, this would give info about the flexibility of dns config and any ease-of-use features offered by AA UI. In the case of email this might include encrypted L5 protocols availability, options for ports, options for SMTP, forwarding/redirecting conditional/unconditional, anti-spam settings, filtering settings, sucking in external mail, server-side rules, other active server-side processing options, availability of easy support for SPF and/or other similar schemes, webmail UI functionality spec. Quite a list, which just goes to show the value of having such a concise checklist-type spec when a prospective customer for email or DNS hosting needs to quickly check off their requirements or when they see a killer feature that you offer that attracts them.