Modify "Sign In" text depending on site status

_**Not to be pulled yet.**_

A quick look at some of the thoughts in #14 (Let's be clear who owns each wiki)

Using the CSS Persona Sign In so message can be varied depending on if the site is owned or not.

Also if the site is owned display the name of the site owner, for now it will just be the name before the '@' in the email address.