Feature/fas upgrade downgrade hide

The links to upgrade and downgrade users seems to have been almost always shown due to using "or" instead of "and" in the conditional.  The logic we want is:

if the targeted user can be upgraded further and the logged-in-person is able to do so, then show the upgrade link.

if the targeted user can be downgraded further and the logged-in-person is able to do so, then show the downgrade link.

This depends on PR#29 due to API updates in the auth.py module.