In short applications, it's possible that the agent (i.e., local rank
0) will finalize after non-local rank 0 procs detect the connectivity
checker named socket, but before they complete a connect() on it. As
such, their connect() gets ECONNREFUSED.
This commit adds a simple counter in the agent that won't let it quit
before it accept()'s from all local procs, or 10 seconds goes by
(whichever occurs first). This is similar to the timeout for the
clients: they'll exit if they don't see the expected named socket
within 10 seconds.
7da1c4b875