remove the cached connection from the upstream retrying function
Merge branch 'develop' into fix_keepalive_retry
added the retry_cached_connection directive
session_sticky_bugfix
Merge pull request #250 from dinic/session_sticky_bugfix1

session_sticky_bugfix
fix the null pointer problem
fix the null pointer problem
Merge pull request #251 from wangbin579/master

Null pointer value stored to 'p'
bugfixed: "buffer" is disabled in access_log
Merge pull request #252 from cfsego/calibaba

bugfixed: "buffer" is disabled in access_log
add validation and roll back feature
1. add large file seg_head validation check
2. roll back write when write failed or client abort
Merge pull request #254 from zhcn381/upstream

add validation and roll back feature
allow to intercept responses with status 300.
Merge pull request #255 from hnlq715/master

Upstream: allow to intercept responses with status 300.
add abi compatibility detective.
update proxy_bind to support variable
update proxy_bind to support variable
The "fastcgi_bind", "uwsgi_bind", "scgi_bind" and "memcached_bind" directives are now inherited; inherited value can be reset by the "off" parameter.  Duplicate directives are now detected.  Parameter value can now contain variables.
Merge pull request #257 from jinglong/bind

update proxy_bind to support variable
bumped version to 1.5.0