Ignore Mac .DS_Store files
Rate limit Spark.publish to 4 events per second
Merge pull request #7 from spark/feature/rate-limit-publish

Rate limit Spark.publish to 4 events per second
Ack server pings for faster closure of half-open sockets
Merge pull request #10 from spark/feature/ack-server-pings

Ack server pings for faster closure of half-open sockets