We were not processing the timeout queue because we got stuck forever in
the loop that processed events. Now before looping back to sysread, make
sure there is something to read so we don't block.

When we startup or re-read the DB state, ignore really old state timeout
values; e.g., for nodes that have been dead for ages but happen to be in
a state such as SHUTDOWN that has a timeout.

In the main loop, handle any re-read of the DB state before testing the
queue length to see if we can do a blocking poll. Re-reading the state may
add timeouts to the queue.