Use MacOSXWatchService instead of PollingWatchService
Use MacOSXWatchService instead of PollingWatchService

This watch service should be more responsive and significantly reduce
the disk overhead of the polling based service for large repos.

mdedetrich/sbt,mdedetrich/sbt,sbt/sbt,xuwei-k/xsbt,xuwei-k/xsbt,xuwei-k/xsbt,sbt/sbt,sbt/sbt,mdedetrich/sbt,xuwei-k/xsbt,sbt/sbt,sbt/sbt,mdedetrich/sbt,mdedetrich/sbt,sbt/sbt,xuwei-k/xsbt,mdedetrich/sbt,sbt/sbt,mdedetrich/sbt