[mod_magnet] lua_tointegerx() avoids raising error
[mod_magnet] lua_tointegerx() avoids raising error

use lua_tointegerx() instead of luaL_optinteger() to avoid raising error
(lua_tointegerx() was introduced in lua 5.2; fallback provided for <5.2)

lighttpd/lighttpd1.4,gstrauss/lighttpd1.4,lighttpd/lighttpd1.4,lighttpd/lighttpd1.4,gstrauss/lighttpd1.4,gstrauss/lighttpd1.4,gstrauss/lighttpd1.4,gstrauss/lighttpd1.4,lighttpd/lighttpd1.4,gstrauss/lighttpd1.4,lighttpd/lighttpd1.4,lighttpd/lighttpd1.4