Slow down sweeper to make sure we receive all messages
Slow down sweeper to make sure we receive all messages

Signed-off-by: Derek Collison <e1c79a582b6629e6b39e9679f4bb964d25db4aa8@nats.io>

apcera/gnatsd,wallyqs/gnatsd,apcera/gnatsd,wallyqs/gnatsd,nats-io/gnatsd,nats-io/gnatsd