RxJava 0.17.1

This version includes a fix needed after testing RxJava 0.17.0 and Hystrix 1.4 on production canaries.
Merge pull request #221 from benjchristensen/rx-0.17.1

RxJava 0.17.1
comment out javadoc
Update build.gradle
eliminate javadoc in build
Fix Future.cancel Unit Test behavior

related to https://github.com/Netflix/RxJava/pull/959
Merge pull request #222 from benjchristensen/unit-test-fixes

Future.cancel - Unit Test Fixes