fixes for MSVC non-standard C library

strcase => _stricmp
strncase => _strnicmp
strdup => _strdup
snprintf => _snprintf

a compliant snprintf() is supposed to be available
in MS Visual Studio 2015 and later

src/windows.c

@@ -31,8 +31,10 @@
 
 #ifdef _MSC_VER
 #include <stdio.h>
+#if _MSC_VER < 1900
 #define snprintf _snprintf
 #endif
+#endif
 
 #include "windows.h"