Fix #68: JS optional arguments via Scala default arguments in interop
Merge pull request #132 from gzm0/default-args

Fix #68: JS optional arguments via Scala default arguments in interop
Implement java.util.concurrent.TimeUnit.

It is used by scala.util.concurrent.duration.Duration.
Merge pull request #134 from jonas/timeunit

Implement java.util.concurrent.TimeUnit.