JUnit setting subscription concurrently
Merge pull request #569 from Netflix/docs

javadoc improvements (groupJoin, groupByUntil, timestamp w/scheduler)
Added release notes for Observer.
Added missing empty implementations for Observer methods.
Release notes
Added overrides.
Strange changes ...
Removing BooleanSubscription
Making tests work
Making tests work.
Solution was to delete all class files.
Why is there no build/clean?
Return null on getSubscription() when previously unsubscribed to match
initial contract
Operation Sample with Observable v2
ObserveOn fix for observing the same source on the same scheduler by two different observers.
Modified Subscription tests.
Modified Subscription tests.
Modified Subscription tests.
Removed Opening and Closing historical artifacts.
Fixed scala compilation error.
remove package rx.lang.scala.util since all its contents were removed
remove import rx.lang.scala.util._
Merge pull request #1 from samuelgruetter/OpeningClosingRemovedSam

remove package rx.lang.scala.util since all its contents were removed