Bump rxjava from 1.0.9 to 1.3.8
Bump rxjava from 1.0.9 to 1.3.8

Bumps [rxjava](https://github.com/ReactiveX/RxJava) from 1.0.9 to 1.3.8.
- [Release notes](https://github.com/ReactiveX/RxJava/releases)
- [Changelog](https://github.com/ReactiveX/RxJava/blob/v1.3.8/CHANGES.md)
- [Commits](https://github.com/ReactiveX/RxJava/compare/v1.0.9...v1.3.8)

Signed-off-by: dependabot-preview[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@dependabot.com>
mmastrac/progscrape-android