Changes with nginx 1.7.2 17 Jun 2014
*) Feature: the "hash" directive inside the "upstream" block.
*) Feature: defragmentation of free shared memory blocks. Thanks to Wandenberg Peixoto and Yichun Zhang.
*) Bugfix: a segmentation fault might occur in a worker process if the default value of the "access_log" directive was used; the bug had appeared in 1.7.0. Thanks to Piotr Sikora.
*) Bugfix: trailing slash was mistakenly removed from the last parameter of the "try_files" directive.
*) Bugfix: nginx could not be built on OS X in some cases.
*) Bugfix: in the ngx_http_spdy_module.