doc: documented the new full-duplex stream cosocket feature.

bumped version to 0.9.8.

doc: now we have tested with nginx 1.5.12; also put the 0.9.7 release…

… date.

bumped version to 0.9.6.

updated docs for the 0.9.5 release.

doc: documented the new ngx.worker.pid() API.

skipped tests that could fail in the "check leak" testing mode.

documented the 5th optional argument, "res_table", for ngx.re.match().

Merge pull request openresty#322 from zh-ang/master

fixed a compilation warning when PCRE is disabled.

doc: bumped version to 0.9.3 and also stated that we work with nginx …

…1.4.4.