BRANCH 4.1:
  added offset and skip_duplicate kwarg to add_initial_tasks() API function
  added prod_setting bid_duration_unit used in add_initial_tasks (minute/hour)
BRANCH 4.1:
  added Search.add_day_filter() expecting a date string for filtering
  updated add_message to only enable with message_event column set for an sType
BRANCH 4.1:
  updated StatusLog to use SearchType.create to create a new status log