Program resilience when the server is shut down #324
Description
When the server is not running for whatever reason, the programs should reiterate their actions periodically or on restart.
For instance, if innd is shut down (rc.news stop) at the same time a NoCeM notice arrives, perl-nocem may not be able to send the cancel command:
ctlinnd: cannot send "cancel" command (sendto failure): No such file or directory
It notably affects programs spawned as newsfeeds sites.