This adjusts 53d592ad by @tgxworld
- Adds Sidekiq.upause_all! to unpause all sites
- Adds Sidekiq.paused_dbs to list dbs that are currently paused
- Handles some edge cases where unpause thread could extend expiry on
sites that were unpaused from a different process
- Ensures tests always terminates background thread used for pause
keepalive