Bugfix/win32 build warnings (#936)

* Changed win32 port of localtime to use secure OS API functions when compiled with MSVC

* Changed all the sprintf to use snprintf instead in BSC tests to ensure null string endings.

ports/win32/bsc-event.c

@@ -10,6 +10,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdbool.h>
+#include "bacnet/basic/sys/debug.h"
 #include "bacnet/datalink/bsc/bsc-event.h"
 
 #define DEBUG_BSC_EVENT 0