changed the modules to use the new BACNet string types.

Modified the device object to handle having the string properties changed via WriteProperty service.
Updated the unit tests.
Updated the demo objects.

bacnet-stack/ai.c

@@ -71,6 +71,7 @@ int Analog_Input_Encode_Property_APDU(
 {
   int apdu_len = 0; // return value
   BACNET_BIT_STRING bit_string;
+  BACNET_CHARACTER_STRING char_string;
   char text_string[32] = {""};
   float value = 3.14;
   
@@ -84,7 +85,9 @@ int Analog_Input_Encode_Property_APDU(
     case PROP_OBJECT_NAME:
     case PROP_DESCRIPTION:
       sprintf(text_string,"ANALOG INPUT %u",object_instance);
-      apdu_len = encode_tagged_character_string(&apdu[0], text_string);
+      characterstring_init_ansi(&char_string, text_string);
+      apdu_len = encode_tagged_character_string(&apdu[0],
+          &char_string);
       break;
     case PROP_OBJECT_TYPE:
       apdu_len = encode_tagged_enumerated(&apdu[0], OBJECT_ANALOG_INPUT);