daemon wakeup idea

[sysadminmike]

When no changes for a while it can take a while before the daemon notices the next change

Perhaps add a field in checkpoint_settings - when sending stuff to couch check after send

• if time is < inactivity time send NOTIFY to daemon to wake up and check for the new changes.
• make inactivity time unique per db and store in checkpoint settings

[sysadminmike]

rename checkpoint_settings to feed_settings