I should be able to preview my System emails

(User Story, Investigate , Priority: High, Test Status: No automated tests yet , Reported By Justin du Coeur, )
Email, System
Summary: Emails are composed as Wikitext, but we don't have a Preview mechanism. This is especially problematic for system-wide emails, which will be seen by everyone.
There should be a Preview button when you compose System emails, so that you can see what they hell you're sending.
This display should specifically include the email CSS stylesheet, so you see the email correctly.