Add non-working day calendars to restrictions in schedules

Current Situation

• Schedules can hold restrictions that allow flexible use of base calendars:
  • Assume a working day calendar Mon-Fri.
  • Assume a schedule restriction for 4th of month.
  • Resulting days are calculated from the working day calendar and the 4th day of the resulting list of days.
• Schedules can hold references to non-working day calendars too.
  • The non-working day calendars are applied to the calculation result of each schedule's restriction.
• If users want to exclude certain non-working days from the calendar before the "4th of month" restriction is applied, then they have to specify such days from the Excluded Frequencies of the working day calendar.

Desired Behavior

• Users would like to find the functionality that a schedule's restriction can be assigned one or more non-working day calendars. This allows to further limit the number of resulting days before other frequenccy types of the restriction will be applied.
• The frequency types offered by the GUI for restrictions as visible from restriction-types.png are extended by the "Non-working Day Calendars" type. The frequency type allows to select one or more non-working day calendars.
• The calculation of the Daily Plan and schedule preview consider the new frequency type by first excluding days from the indicated non-working day calendars and then apply remaining frequency types of a restriction.

Test Instructions

• Tests using Preview
  • Create a Working days calendar that uses a Non-working days calendar under "Excluded Frequencies".
    • Example:
      • Working days calendar: includes every day
      • Non-working days calendar: includes weekends (Sun, Sat)
      • Check calendar Show Preview:
        • Expected result: Non-working days calendar dates are excluded from the Calendar Preview.
  • Create a new Schedule:
    • Test with “Assign Working Day Calendar”: select the previously created and released calendar.
      • Show Preview:
        • Expected result: Non-working days calendar dates are excluded from the Schedule Run-time view.
    • Add a Restriction: Month Days -> 1st of the month.
      • Show Preview:
        • Expected result: The 1st of the month is treated as the first working day of the month.
    • Check other restriction types.
  • Tests using Restriction
    • “Assign Working Day Calendar”: use a “normal” every-day calendar without exclusions.
    • Add a Restriction: Non-Working Days Calendars.
      • Show Preview:
        • Expected result: Non-working days calendars dates are excluded from the Schedule Run-time view.
    • Add an additional Restriction: Month Days -> 1st of the month.
      • Show Preview
        • Expected result: The 1st of the month is treated as the first working day of the month
    • Check other restriction types.
  • Non-Working Days Calendar: set validity period
    • Set “Valid From” and “Valid To” in the Non-Working Days Calendar to a past time period.
      • Expected result: The non-working days are ignored in all test cases.
  • Tests using multiple Non-working days calendars 
• Tests using Daily Plan
  • The created Daily Plan entries should match the expected dates.