Migrate code to use rx.schedulers instead of rx.concurrency
Migrate code to use rx.schedulers instead of rx.concurrency

Unit tests passed before and after (did change in multiple steps to assert unit test pass against rx.concurrency before migrating to rx.schedulers).

aaronzirbes/RxGroovy,aaronzirbes/RxGroovy,ReactiveX/RxGroovy,ReactiveX/RxGroovy