javadoc changes to correspond with recent method changes
more javadoc changes to correspond with recent method changes
Fix TrampolineScheduler NullPointerException

I tried for about 30 minutes to replicate the NPE reported in https://github.com/ReactiveX/RxJava/issues/1702 but couldn't.
It makes sense reading the code that an unsubscribe could trigger an NPE though so I'm fixing it as per recommendation of @DylanSale even though I can't replicate.
I confirmed that the items are being put in the queue BEFORE the wip variable is incremented, so that concurrency seems okay.
Remove use of ThreadLocal

This was an awkward leftover from early version of RxJava (pre v0.17).
Delay Operator with Reactive Pull Backpressure

Updated the implementations to support reactive pull backpressure.
Fixes https://github.com/ReactiveX/RxJava/issues/1724
Fix Slow Non-deterministic Test

Somehow I missed the Thread.sleep to force the scenario so most of the time this test would run very slow (or forever).
I'm surprised the unit tests passed before... just random luck on thread scheduling.
Merge pull request #1739 from benjchristensen/observeOn-testErrorPropagatesWhenNoOutstandingRequests

Fix Slow Non-deterministic Test
Merge pull request #1738 from benjchristensen/issue-1724

Delay Operator with Reactive Pull Backpressure
Merge pull request #1736 from benjchristensen/issue-1702

Fix TrampolineScheduler NullPointerException
longCount -> countLong

Fixes https://github.com/ReactiveX/RxJava/issues/1684
Merge pull request #1740 from benjchristensen/countLong

longCount -> countLong
Delete EmptyObserver

It creates no value and confuses with Observers.empty() which throws an OnErrorNotImplementedException if onError is invoked.
Fixes https://github.com/ReactiveX/RxJava/issues/1741
Clarify Javadoc on Observers.empty()

It throws an Exception ... and now EmptyObserver is gone.
Swallow Errors in TestObserver

If a delegate is not provided then do nothing.
Fixes https://github.com/ReactiveX/RxJava/issues/1571
Merge pull request #1742 from benjchristensen/issue-1571

EmptyObserver and TestObserver
Subject Error Handling

Fixes https://github.com/ReactiveX/RxJava/issues/1685 by delaying errors that are caught until after all subscribers have a chance to receive the event.

Note that this has a lot of code duplication to handle this across the Subject implementations. It may be worth abstracting this logic ... but right now I'm just doing what makes sense to fix this as the Subject abstractions are non-trivial.
Merge pull request #1743 from benjchristensen/issue-1685

Subject Error Handling
SerializedSubject

See https://github.com/ReactiveX/RxJava/issues/1744
Fatal System.err Logs on Unhandled Exceptions

If an exception is thrown on a thread then we can't do anything with it so will log out to System.err.

Fixes https://github.com/ReactiveX/RxJava/issues/1682 ScheduledAction Swallows Errors
Merge pull request #1746 from benjchristensen/issue-1682

Fatal System.err Logs on Unhandled Exceptions