As setitimer() isn't available on Windows, time wasn't updated at all
if timer_resolution was used with the select event method.  Fix is
to ignore timer_resolution in such cases.

This context is needed for shared sessions cache to work in configurations
with multiple virtual servers sharing the same port.  Unfortunately, OpenSSL
does not provide an API to access the session context, thus storing it
separately.

In collaboration with Vladimir Homutov.

If no space left in buffer after adding formatting symbols, error message
could be left without terminating null.  The fix is to output message using
actual length.

RAND_pseudo_bytes() is deprecated in the OpenSSL master branch, so the only
use was changed to RAND_bytes().  Access to internal structures is no longer
possible, so now we don't try to set SSL3_FLAGS_NO_RENEGOTIATE_CIPHERS even
if it's defined.

OCSP responses may contain no nextUpdate.  As per RFC 6960, this means
that nextUpdate checks should be bypassed.  Handle this gracefully by
using NGX_MAX_TIME_T_VALUE as "valid" in such a case.

The problem was introduced by 6893a1007a7c (1.9.2).

Reported by Matthew Baldwin.

Broken by 6893a1007a7c (1.9.2) during introduction of strict OCSP response
validity checks.  As stapling file is expected to be returned unconditionally,
fix is to set its validity to the maximum supported time.

Reported by Faidon Liambotis.

The change was missed in f69d1aab6a0f.