bugfix when use chrome and safari.
Merge pull request #281 from taoyuanyuan/t

Bugfix: fixed a bug of trim module.
added request_non_buffered feature to http proxy and fastcgi module

Now the request body can be passed chunk by chunk to upstream, while
the whole body need be buffered before.
Merge pull request #285 from yaoweibin/request_no_buffering3

added request_non_buffered feature to http proxy and fastcgi module
added the Changelog for tengine-1.5.0
Merge pull request #286 from yaoweibin/tengine-1.5.0-2

added the Changelog for tengine-1.5.0
Merge branch 'master' of github.com:alibaba/tengine