CombineLatest fix
Moved onError, onCompleted and cancel.unsubscribed outside the lock
adjust javadocs for new sumFoo()/averageFoo() method names
Merge pull request #705 from Netflix/docs

adjust javadocs for new sumFoo()/averageFoo() method names
New contrib module: rxjava-async-util

Home for async utility functions with juc.Future, Actions, Functions etc that don’t need to be in rxjava-core.

As per discussions at:

- https://github.com/Netflix/RxJava/pull/646#issuecomment-31147005
- https://github.com/Netflix/RxJava/pull/645#issuecomment-31146492
- https://github.com/Netflix/RxJava/pull/622#issuecomment-31144128
Manual merge of https://github.com/akarnokd/RxJava/commit/eee312a6ac41582e4efe3daac3dfcd0385359d25

- To clean up the pull request I cherry picked the single commit with actual changes to avoid the merges that affected lots of other files.
- The original commit also included conflicting and unrelated changes to Observable and ObservableTests that I skippedManual merge of https://github.com/akarnokd/RxJava/commit/eee312a6ac41582e4efe3daac3dfcd0385359d25
Merge pull request #707 from benjchristensen/rxjava-async-util-module

Merge of rxjava-async-util
Merge branch 'CombineLatestFix' of github.com:akarnokd/RxJava into combine-latest
Manual Merge of Pull #616

Manual merge of https://github.com/Netflix/RxJava/pull/616

- remove use of SingleAssignmentSubscription
- suppress warnings
Merge pull request #708 from benjchristensen/combine-latest

Combine latest fix
Lotsa javadoc improvements
* diagrams for previously-undiagram'd methods
* links to wiki docs where available
* standardizing format & nomenclature
Merge pull request #709 from Netflix/docs

Lotsa javadoc improvements
Created new wiki page for the operators in the Async class
...adjusted javadoc links accordingly
...added new sections for previously un-wiki-documented operators in Async
...added links to those in javadocs
Merge pull request #710 from Netflix/docs

Created new wiki page for the operators in the Async class