Build option for Lua events that is off by default.

src/platforms/core_desktop.c

@@ -649,5 +649,7 @@ void luaPlatformRegister() {
 
 	lua_pop( L, -1 );
 
+#ifdef LUA_EVENTS
 	platformRegisterEvents();
+#endif
 }

src/platforms/core_desktop_sdl.c

@@ -555,5 +555,7 @@ void luaPlatformRegister() {
 
 	lua_pop( L, -1 );
 
-	platformRegisterEvents()
+#ifdef LUA_EVENTS
+	platformRegisterEvents();
+#endif
 }