bugfix: when lua_code_cache was off, cosocket:setkeepalive() might lead to segmentation faults. thanks Kelvin Peng for the report.
refactor: we no longer call ngx_pfree() in our own pcre_free hook.
added assertions for the pcre pool management.
bumped version to 0.9.7.
Update ngx_http_lua_string.c
Merge pull request #355 from lhmwzy/master

Update ngx_http_lua_string.c to fix a typo in an error message.