This package adds support to register users for things.

• The page workflow to add/remove and go back and update is really rough and needs updating
• on install, add folders and mark interfaces where needed
• Remove [read:hide] Food option
• Ask about people bringing families and if they would be interested in a set of coordinated activities for them (# of kids too?)
• update badge types
• email.py needs to use server configure with mailhost and not netsights url
• Can we pull ploneorg user information into the registration form? to prefill?
• don't need subtotal/tax in carts
• Items in cart should have attendee name but now its empty

• seems like the conference registration email should be sent after payment confirmation?
• Put conference year configuration in something more sane, or at least just add a control panel.