Add getChoice to ChoiceField

This allows for subclasses to define how the choice is formatted.
Split ticket status states into public and private
Remove internal ticket states from user space

Reserve 'archived' state for automation
Support custom statuses deletion

Statuses with tickets cannot be deleted
Fix orm to class gracefully when joins are not inspected
Add create date to new statuses
Support ticket deletion

Delete tickets for realz when set to 'deleted' status. This commit will be
partially reverted once data retention plugin is added.
Support loading spinner on generic popup dialog

Empty the popup container and show loading spinner
on-load hide the spinner and show the content
Use generic dialog popup on items config

Unify use of modal dialog
Makde popups graggable
Drop ticket flags data

Flags will be reimplemented as a separate feature.