OperationAll to OperatorAll
Reimplement the 'single' operator
Add first, last, single to rxjava-scala
Throw NoSuchElementException in the first, last and single operators when the Observable is empty
Rename OperationFirstOrDefaultTest and OperationLastTest to OperatorFirstOrDefaultTest and OperatorLastTest
Fix clojure test
Fix tests in rxjava-math
Fixed deadlock in Subjects + OperatorCache.
Merge branch 'master' into single
Fix typos
add toMap from Java Observable
add examples of toMap to RxScalaDemo

Added examples for all three overloads and removed newlines between
methods and docs
corrected implementation

Implementation corrected to not raise exceptions
Adding a new RetainedFragment example
Remove Redundant protectivelyWrap Method
Merge pull request #1015 from benjchristensen/safe-subscribe

Remove Redundant protectivelyWrap Method
unsubscribe before retry
Unsubscribe on retry using SerialSubscription
Merge pull request #1019 from benjchristensen/retry-1018

Fix: retry() never unsubscribes from source until operator completes
[Gradle Release Plugin] - pre tag commit:  '0.17.5'.