Raise a ParseError exception if not.

Fixes #1885.

Fixes #1869

OK'd by phk@.

Fixes #1883.

Fixes #1918.

Submitted by:	Pål Hermunn Johansen

All bans on olist can get marked completed as duplicates while we're
working on them, in particular as we start at an offset of
ban_lurker_age.

Fixes #1919

Fixes a bug where we wait for an event to fire on the backend socket
prior to passing the request body.

The VBT_Wait call is now handled in vbe_dir_finish.

Test case by thomaslc

Fixes: #1806

Updated formatter %{VSL:tag}x to mirror the VQL. The documentation has
been updated accordingly.

The formatters %{Varnish:vxid}x and %{VSL:key[:field]} are introduced,
with documentation. Also updated copyright in the varnishncsa.c file.

Fixes #1912

A new mode, backend mode, in varnishncsa is introduced. It lets you
log trafic from varnish to the backends. The normal (default) mode is
now named "client mode" and can be explicitly selected using -c. You
can run varnishncsa in backend mode in addition to varnishncsa in
client mode, but it is also possible to run in mixed mode by
specifying both -b and -c.

New formatter added: %{Varnish:side}x will be either "b" or "c",
depending on where the request was made.

This log record is a counterpart to the SLT_ReqStart for backends, and
shows the socket endpoint we are talking to at the start of backend
requests. Today this information is only logged on opening a backend
connection (SLT_BackendOpen), and is thus not available on the backend
log transaction when on a reused backend connection.

We need this information to complete the backend view varnishncsa
extension.

When the VEP state machine is in a bad state during finalization
(VEP_Finish), we log this as an ESI error.

When an ESI tag contains an unterminated quote or misses its ending
'>', we release the relevant buffers instead of crashing.

Fixes: #1904

Discussed with Federico.

Fixes: #1725

When ESI delivering a gzip'ed object, emit the GZIP header+tail
precisely if no parent ESI has done so.

Fixes:	#1878
Testcase by:	fgs

They're part of the tree now.

This fixes a problem when a backend replies with 304 Not Modified
(after a http conditional request from varnish) and does not supply a
header that was duplicate in the cached object.

Before this patch, varnish would only supply (by copying from the
expired object) the first instance of a duplicate header.

There's a recurring pattern throughout the code base of taking over
a reference (by nulling the original) essentially when resources are
freed. Instead of repeating this anti dangling pointers measure, it
can be wrapped in a documenting utility macro.

Fixes #1871

This really is the wrong way to go, generated files should not live
in the source tree. But lightening the load of phk is more important.

to remove the dependency on graphviz when building from a tarball

Fixes:	#1860