parsing ''salt-call -d'' was pretty errorprone and it finally broke. :D
Documention for some cron.* file.* functions isn't formatted with
leading whitespace, thus are picked up by the completer.
So now the completer parses salt-call sys.list_(runner_|)functions
allows a user to control how long to keep various caches without
defining their own function to override ours.
The default duration was changed from 7 days to 1 day. which seems a bit
more useful for people who don't have a static number of hosts like
myself.
