Refactor/ports xplained common dlmstp (#665)

* Refactored ports/xplained to use common DLMSTP module to enable extended frames

* Added floating point compares in cases where they don't exist in math library

ports/xplained/Makefile

@@ -45,7 +45,6 @@ CSRC = main.c \
 	bacnet.c \
 	bname.c \
 	device.c \
-	dlmstp.c \
 	led.c \
 	mstimer-init.c \
 	netport.c \
@@ -79,7 +78,6 @@ BASICSRC = $(BACNET_BASIC)/tsm/tsm.c \
 
 # core BACnet stack files
 CORESRC =  \
-	$(BACNET_CORE)/datalink/crc.c \
 	$(BACNET_CORE)/abort.c \
 	$(BACNET_CORE)/bacaddr.c \
 	$(BACNET_CORE)/bacapp.c \
@@ -90,9 +88,15 @@ CORESRC =  \
 	$(BACNET_CORE)/bacreal.c \
 	$(BACNET_CORE)/bacstr.c \
 	$(BACNET_CORE)/datetime.c \
+	$(BACNET_CORE)/datalink/cobs.c \
+	$(BACNET_CORE)/datalink/crc.c \
+	$(BACNET_CORE)/datalink/dlmstp.c \
+	$(BACNET_CORE)/datalink/mstp.c \
+	$(BACNET_CORE)/datalink/mstptext.c \
 	$(BACNET_CORE)/dcc.c \
 	$(BACNET_CORE)/iam.c \
 	$(BACNET_CORE)/ihave.c \
+	$(BACNET_CORE)/indtext.c \
 	$(BACNET_CORE)/memcopy.c \
 	$(BACNET_CORE)/hostnport.c \
 	$(BACNET_CORE)/npdu.c \