Added support for Visual Studio 2015.

Fixed some WIN32 specific compile issues.
Changed MinGW build to use _NO_OLDNAMES so that it compatible with MSVC.
Thank you John LaFontaine for the contribution!

bacnet-stack/demo/object/gw_device.c

@@ -61,7 +61,7 @@
 /* os specfic includes */
 #include "timer.h"
 
-#if defined(__BORLANDC__)
+#if defined(__BORLANDC__) || defined(_WIN32)
 /* seems to not be defined in time.h as specified by The Open Group */
 /* difference from UTC and local standard time  */
 long int timezone;
@@ -79,8 +79,12 @@ bool Routed_Device_Write_Property_Local(
 
 
 #if !defined(BAC_ROUTING)
+#ifdef _MSC_VER
+#pragma message This file should not be included in the build unless BAC_ROUTING is enabled.
+#else
 #warning This file should not be included in the build unless BAC_ROUTING is enabled.
 #endif
+#endif
 
 /****************************************************************************
  ************* BACnet Routing Functionality (Optional) **********************