Many, many times, I've been debugging things happening on my machine where it 
would have been extremely helpful to know exactly when a specific job executed 
by run-parts had been running.  Alas, although cron or anacron logs when it 
starts run-parts, run-parts itself doesn't log when it starts and ends jobs.  
The attached patch fixes this.

(While we're on the topic, I think it's unfortunate that cron only logs when 
jobs start, not when they finish, but that's a topic for a different bug 
report).