Method: Intended to run when the save_post_tribe_events action is fired.

Method: Fires on delete_post and decides whether or not to rebuild our record or earliest/latest event dates (which will be done when deleted_post fires, so that the deleted event is removed from the db before we recalculate).

Method: Intelligently updates our record of the earliest start date/latest event date in the system. If the existing earliest/latest values have not been superseded by the new post’s start/end date then no update takes place.

Method: The class singleton constructor.

Method: Determine the earliest start date and latest end date currently in the database and store those values for future use.