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>

test/bacnet/bacdcode/CMakeLists.txt

@@ -38,6 +38,8 @@ add_executable(${PROJECT_NAME}
 	${SRC_DIR}/bacnet/bacint.c
 	${SRC_DIR}/bacnet/bacreal.c
 	${SRC_DIR}/bacnet/bacstr.c
+	${SRC_DIR}/bacnet/datetime.c
+	${SRC_DIR}/bacnet/basic/sys/days.c
 	${SRC_DIR}/bacnet/basic/sys/bigend.c
     # Test and test library files
 	./src/main.c