modified process-new and all related stuff so NEW can now also be processed
during (most of) dinstall. The lock where NEW is forbidden is then down to
some 15 til 20 minutes, instead of 2 hours.

For that process-new moves files into a "staging" directory, from which
cron.unchecked will move them into the accepted queue. As c.u only runs when
it is safe to do so this is fine.

The small part where we still are forbidden to do NEW is between the point where
we run process-accepted and right before we start generating Packages files. As
that is exactly the area daily.lock exists for, process-new now locks on that and
simply refuses to do work then.
Signed-off-by: NJoerg Jaspert <joerg@debian.org>