There are many derived values that do calculations based on the
raw metrics, done in the status() message.  By moving these
calculations to the _resolve() routine, we make the results available
to sr overview and sr dump, and this provides a foundation for more
refined running states, as per #824

There is a weird timeout error caused by setting timers that
are never cleared when errors occur. this causes subscriber to
crashes when FTP file retrieval fails, rather than logging and
continuoing.

Also added logProgress routine which is called to print a log
message often enough to satisfy sanity_log_dead. currently fixed
at every 60 seconds during a transfer.

This code says the instances we find that don't have pids, are missing.
This happens when we read metrics, and then know what the pids of the
flows were when it was last running.
An instance pid that doesn't have a matching file is actually a stray.
I think this code pre-dates strays. anyways what was happenning:

sr3 stop xx   # xx has current metrics file.
sr3 sanity
  # instances of xx are detected as "missing" because metrics present.
  # sanity therefore starts up xx when it should not.

With this change, the cleanup() routine now returns a boolean, True for
success, False for failure.   so remove() now only proceeds if cleanup()
reports success.

Also, cleanup will do nothing unless all the configurations chosen are stopped.
Formerly it would clean up the stopped configurations, and skip the others.