Feature/what is network number handling (#304)

* Add What-Is-Network-Number handling.

Add What-Is-Network-Number and Network-Number-Is network layer handling.
Refactor npdu_encode_npdu_network() from router specific code.
Add unit test for NDPU network message
Add app for What-Is-Network-Number
Add app for Network-Number-Is
Add send helper for What-Is-Network-Number
Add send helper for Network-Number-Is

* added sys/debug.c to ports builds for use of debug_printf() in npdu handler.

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

ports/bdk-atxx4-mstp/Makefile

@@ -110,6 +110,7 @@ BASICSRC = $(BACNET_BASIC)/service/h_dcc.c \
 	$(BACNET_BASIC)/service/s_iam.c \
 	$(BACNET_BASIC)/service/s_ihave.c \
 	$(BACNET_BASIC)/sys/bigend.c \
+	$(BACNET_BASIC)/sys/debug.c \
 	$(BACNET_BASIC)/sys/fifo.c \
 	$(BACNET_BASIC)/sys/mstimer.c \
 	$(BACNET_BASIC)/sys/ringbuf.c \

ports/bdk-atxx4-mstp/bacnet.cproj

@@ -427,6 +427,10 @@
       <SubType>compile</SubType>
       <Link>BACnet Core\reject.c</Link>
     </Compile>
+    <Compile Include="..\..\src\bacnet\basic\sys\debug.c">
+      <SubType>compile</SubType>
+      <Link>BACnet Core\debug.c</Link>
+    </Compile>
     <Compile Include="..\..\src\bacnet\basic\sys\mstimer.c">
       <SubType>compile</SubType>
       <Link>BACnet Core\mstimer.c</Link>

ports/bdk-atxx4-mstp/bacnet.ewp

@@ -4309,6 +4309,9 @@
     </group>
     <group>
         <name>BACnet Basic Sys</name>
+        <file>
+            <name>$PROJ_DIR$\..\..\src\bacnet\basic\sys\debug.c</name>
+        </file>
         <file>
             <name>$PROJ_DIR$\..\..\src\bacnet\basic\sys\fifo.c</name>
         </file>