to avoid some pointless double-buffering.

While here also drop synopsis indentation.

Prompted by #1681

frob the file after open.

jail_unix makes the file varnish:varnish 0600

around socket operations which may be on reserved ports.

Neuter solaris jail entirely on platforms which don't have it.

Spotted by xavier on irc.

Thanks to Dridi Boukelmoune <dridi.boukelmoune@zenika.com> for spotting typos

The retires the -u and -g arguments, and the user/group/group_cc
parameters, so that the jail-setup cannot be manipulated from CLI at all.

$user and group_cc are now sub-arguments to -junix, for instance:

	-junix,user=varnish1,ccgroup=ccowner

There is no group= subargument, the group information is taken
from the user id in question.

If no -j argument is specified, attempt:

	-junix,user=varnish

but fail silently if not possible.

The "vident" now contains information about jail-config.

Sandbox_solaris is not converted yet, (I'm hoping that Nils will
help with that.

When no -j argument is specified, walk the list to get the most
capable jail technology which can run in the given circumstances.

Due to our somewhat spendthrift ways with argument letters, it
is not realistic to repurpose -[sS]andbox or -[pP]rivsep argument
letters, so the terminology ended up being "jail" because -j was free.

Right now no jails are implemented, and the code does nothing.

Timeout_req was measured from t_idle(which could be either the moment
the connection was accepted or the time of the last activity of the
previous request on the same connection)

Timeout_req, according to the definition(varnishd/mgt/mgt_param_tbl.c)
is now measured starting from t_first(timestamp for the
first byte received).

both introduced yesterday.

already set up in mgt_main.

This state could be set by the expiry timer even though a reference is
grabbed during lookup, causing the assertion to trigger.

Fixes: #1539