delay reload run if last command exited with a bad status

[jmhodges]

No description provided.

[jmhodges]

This will need Reload to return an error only from cmd.Start or if a cs.waitChan() returns a non-nil error. The waitChan part is tricky because it's intentionally private because if we allowed reloads to happen while the waitChan goroutine was running, we might get bad data.

Actually, we might be able to add a method that just checks if waitErr != nil when a watcher event coming over cmdCh to see if it should wait a bit longer by using similar code to what's there now to delay.