An attempt to nuke a busy object will end in assertion.

objects.

This avoids a memory race on the n_sess counter, which can lead to
excessive session object allocation. Keeping the counters of in use
and released separate allows the acceptor to continue to run lockless.

Fixes: #897

Patch by: tnt

Fixes	#1100

Conflicts:

	bin/varnishd/cache_fetch.c
	bin/varnishd/cache_panic.c

Conflicts:

	bin/varnishd/cache/cache_esi_fetch.c
	bin/varnishd/cache_fetch.c
	bin/varnishd/cache_gzip.c

Submitted by:	Martin
Fixes		#1140

Fixes a case where we might get a cache hit even though hash_always_miss is set.

Fixes: #1073

Fixes #1035

Implemented more or less as described in the pcrejit(3) manpage, and
adds some compatibility defines for use with older pre-8.20 libraries
that do not have this functionality.

Fixes: #1080

Fixes #1122

Fixes #1069

argument to a printflike function.

Needed to test #1123

Varnishtest doesn't see the difference between a VCC core dump and
a VCC error, so a test-case is non-trivial.

Fixes	#1126

Fixes #1125

The following patch allows the autoconf script to detect the presence of
libedit when there isn't a pkg-config file present and thus allowing
Varnish to detect libedit on OpenBSD/FreeBSD/NetBSD/DragonFly.

Fixes: #1003

I've opted for a less intrusive fix that Martin proposed, but my fix
is largely a rework of his suggested patch.

Testcase by:	Martin