close and open actions for plain opening and closing the tickets
respond_with so fields are not cleared on invalid update

the custom actions are not strictly restful. But adding a subresource felt like too much overhead and is conceptually hard to grasp (so we destroy the openess of the ticket to close it?).

This controller does too much - so the tests are also getting large and hard to keep track of

Ticket.is_creator_vlidated? now actually fetches the user from the db and returns false if it does not exist.

email and regarding user fields can be set to defaults based on
created_by user.

If these fields are emptied by the submitting user they will be set to  whereas they are nil if they have not been initialized. In that case we will use meaningful defaults from the user who created the ticket.

We should respect the users choice. We can still get their email from the user id if we really need to.

Also renamed help to support so it's harder to confuse it with documentation