1022013 - wait until subs apply before refreshing lists

On the system subscriptions page, the subscription lists were being
refreshed as soon as the request to add/remove subs was sent. On
a multi-process production install, this would result in subs showing
up in a list when they should not
Merge pull request #3265 from jlsherrill/1022013

1022013 - wait until subs apply before refreshing lists