Implement missing data types for calendar and schedule (#474)

* Added the SpecialEvent struct for the Exception_Schedule property of Schedule, encode/decode/same functions, unit tests, and integrated into bacapp functions.

* Added the CalendarEntry struct for the Date_List property of Calendar and the SpecialEvent struct, encode/decode functions, unit tests, and integrated into bacapp functions.

* Added the DateRange struct for the Effective_Period property of Schedule, encode/decode functions, unit tests, and integrated into bacapp functions.

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Co-authored-by: Steve Karg <skarg@users.sourceforge.net>

zephyr/tests/bacnet/basic/object/objects/CMakeLists.txt

@@ -51,6 +51,8 @@ if(BOARD STREQUAL unit_testing)
     ${BACNET_SRC}/hostnport.c
     ${BACNET_SRC}/dailyschedule.c
     ${BACNET_SRC}/weeklyschedule.c
+    ${BACNET_SRC}/calendar_entry.c
+    ${BACNET_SRC}/special_event.c
     ${BACNET_SRC}/basic/sys/bigend.c
     ${BACNET_SRC}/bactimevalue.c
     )