Move string natives from logic to core (bug 4406 part 8, r=fyren).

--HG--
rename : core/smn_string.cpp => core/logic/smn_string.cpp

core/logic_bridge.cpp

@@ -137,6 +137,7 @@ static sm_core_t core_bridge =
 	UTIL_Format,
 	generate_error,
 	gnprintf,
+	atcprintf,
 	&serverGlobals
 };