Add many more fields to the EAD export (and fix some bugs)
Eat some ugliness in order to get more detail into the repository address info
Bow to inevitable and add EAD physloc as a separate field
Prevent paragraphs from being rendered within list items
Various EAD fixes courtesy of Tim and the APE preparation tool.
Make related material multi-valued, and add sources field
Lots of enhancements to the linking functionality.
 - allow editing existing links
 - add an option to link historical agents
 - add link type to link form
 - add dates to link and form
Clean up rendering of related links in access points
Consolidate rendering of links
Add convenience method to Hierarchical trait
Some refactoring of EAD export templates
Remove defunct test
A few more tweaks to EAD
Tiny tidy-up
More EAD refactoring
More EAD refactoring/renaming
Break out EAD conversion into a separate class for easier testing.
Add test to ensure valid EAD XML is generated.
Clean up auth code and use 403 over 401 where appropriate.

As [this](http://stackoverflow.com/a/6937030/285374) answer explains,
we should only use 401 UNAUTHORIZED when the user is not logged in and
the situation is temporary. 403 FORBIDDEN should be used when the user
is logged in but doesn't have the correct permission.
Test cleanup
Part 1 of epic relation cleanup and refactoring.

There are three distinct types of relationships (currently):
 * external (i.e another item's access points point to this one - rename "incoming"?)
 * access point (access points is body for a link)
 * annotation (both items are connected somehow, not via access points)

The display for this on the portal needs much work still.