Add admin<->account navigation

This commit adds an additional element to each logged-in top nav-bar:

 1. On the Admin Area pages, there will be a link to "My Account" which navigates to the account settings area.
 2. On the "My Account" area pages, **iff** the user has a linked administator role, there will be a link to the Admin Area.

This change makes the site easier to use and aids discoverability and design comprehension for newcomers to the project.