Added CharacterString Value object example and unit tests, and added to demo/server example application.

Added Multi-state Value object example and unit tests, and added to demo/server example application.
Fixed Analog Input object, Analog Output object, Analog Value object, Device object, Multi-state Input object, Multi-state Output object examples to return correct error codes for WriteProperty service (per BACnet 135.1-2009-9.22.2.6).
Fixed top level ReadProperty and WriteProperty handlers in Device object to return correct error codes (per BACnet 135.1-2009-9.22.2.5)

bacnet-stack/demo/object/ms-input.h

@@ -72,6 +72,13 @@ extern "C" {
     bool Multistate_Input_Present_Value_Set(
         uint32_t object_instance,
         uint32_t value);
+
+    bool Multistate_Input_Out_Of_Service(
+        uint32_t object_instance);
+    void Multistate_Input_Out_Of_Service_Set(
+        uint32_t object_instance,
+        bool value);
+
     bool Multistate_Input_Description_Set(
         uint32_t object_instance,
         char *text_string);
@@ -89,7 +96,7 @@ extern "C" {
 
 #ifdef TEST
 #include "ctest.h"
-    void testMultistateOutput(
+    void testMultistateInput(
         Test * pTest);
 #endif