Solaris related fixes:
*) Detect POSIX semaphores in librt on Solaris (ticket #3).
Patch by Denis Ivanov.
*) Lower optimization level for Sun Studio before 12.1.
At least Sun Studio 12 has problems with bit-fields exposed by nginx code
(caught by test suite). They seems to be fixed in Sun Studio 12.1. As a
workaround use "-fast -xalias_level=any" for older versions, it resolves
the problem.
*) Feature: the Sun Studio 10 C compiler support.
*) Feature: the "proxy_upstream_max_fails",
"proxy_upstream_fail_timeout", "fastcgi_upstream_max_fails", and
"fastcgi_upstream_fail_timeout" directives.