Add support for underprivileged users submitting entries as "disabled"

[bobharner]

(After authentication & authorization mechanisms are in place) we need to add the ability for a non-admin person to submit a new entry. Maybe they have to create an account, or maybe they just answer a CAPTCHA prompt, not sure. But once they submit, the new entry should be stored as "disabled" and an e-mail sent to the set of users who have the ability to approve submissions. The e-mail should have a link that takes them right into the app to view the entry, and they can then click the "enabled" checkbox and press the Save button.

It would be nice if the original submitter were recorded as the "owner" of the entry and can subsequently edit that entry without further approval.

As part of all this, any edits to any entries at any time should result in a notification e-mail sent to those same approving users. Maybe this would be part of a larger subscribe-to-change-notifications mechanism that anyone could sign up for.