should be adjustable at runtime.

We need to make adjustments in such a way that a restart of the child also
uses the new paramters.

We can either do this by parsing the CLI in both mgt+child and have both
update their private copy, or we can parse it only in one of them and
update a shared copy.

We opt for the latter method.

Add a "struct params" which holds the adjustable parameters and put on
in the shmlog segment, between struct shmloghead and the round-robin
buffer.

Move parameters from heritage to params.

We put it there without exposing it in struct shmloghead which is
the public view of the shared memory because we do not want to make
it a public API or even to tempt people to think that it is one.

Now I just need to add the CLI functions to actually twiddle the
parameters.



git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@835 d4fa192b-c00b-0410-8231-f00ffab90ce4