Fix links to EchoServer.scala
Fixed misnamed barrier
Merge pull request #1357 from etaty/patch-1

Fix links to EchoServer.scala
also fix java/io.rst link to EchoServer et al
Merge pull request #1360 from drewhk/wip-3242-remotenodedeathwatchslow-failed-drewhk

Fixed misnamed barrier
Udp tests now use port acquired from a DatagramSocket #3245
Merge pull request #1358 from drewhk/wip-3245-udp-temporary-address-drewhk

Udp tests now use ports acquired from a DatagramSocket