added external deps

external/easylogging++/ea_config.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include <limits.h>
+
+#define ELPP_THREAD_SAFE
+#define ELPP_DEFAULT_LOG_FILE ""
+#define ELPP_DISABLE_DEFAULT_CRASH_HANDLING
+#define ELPP_NO_CHECK_MACROS
+#define ELPP_WINSOCK2
+#define ELPP_NO_DEBUG_MACROS
+#define ELPP_UTC_DATETIME
+
+#ifdef EASYLOGGING_CC
+#if !(!defined __GLIBC__ || !defined __GNUC__ || defined __MINGW32__ || defined __MINGW64__ || defined __ANDROID__ || defined __NetBSD__)
+#define ELPP_FEATURE_CRASH_LOG
+#endif
+#endif