Partially reverts dc1059da.

	---- c1   11.6 EXPECT resp.http.ageB (11.867) >= "8.000" failed

the waiter still has a FD to work with.

Fixes #1462

all of them find out on their own.

a little bit on Linux.

This should solve the problem of old stale backend connections, as the
waiter will discover the backend closing their end.

A default timeout of one minute from our end is hardcoded for now,
it will be VCL configurable once I make it over to the VCC.

For now a lot of debugging VSL's have been left in, until we see
how much trouble this causes...

and always set it in varnishtest

Spotted by: scn

vary length

also work.

Spotted by Kristian.

two private members.

Check the now miniobj-ified structs from VCC.

takes effect.  Use this to move backend probes as appropriate.

This also retires the vbc_mempool, which doesn't seem to improve things.

Spotted by Coverity.

malloc space: we leak memory while we collapse.

This updates the last oustanding document to 4.0