bugfix: we incorrectly returned 500 in our output header filter, body filter, and log-phase handlers upon inlined Lua code loading errors. bugfix: Lua stack overflow might happen when we failed to load inlined Lua code from the code cache.
bugfix: the "connect() failed" error message was still logged even when lua_socket_log_errors was off. thanks Dong Fang Fan for the report.
Merge remote-tracking branch 'agentzh/master' into getlifetime
getlifetime: remove unuse var on test
getlifetime: remove unnecessary lines on config