* Adding category "Attended" to the courses_terms/view
* Allowing via viewmodel switching states dynamically.
* Notice that the Attendance state is different from the booking state
and to show the attendee unter "attended" you only need to change his
attendance state while leaving the booking state untouched.
* All controllers now inherit the instance variable $setting which
contains all key values from the settings table.
* Getting email configuration based on the debugging mode, during
development a test account is used.
* Allowing assistants for now to access admin areas.
* Adding locking functionality for trainings.
* If attendees have been cleared that now shows up in the interface in
their login area.
* Adding "locking signups" functionality to the admin settings. If
signups are locked the users get redirected to the "locked" view.
* Adding "lock_signups" key value to the settings table schema
definition.