Remove more gradle remnants.
Remove more gradle remnants.

zhongdj/RxScala,jbripley/RxScala,samuelgruetter/RxScala,ReactiveX/RxScala,joohnnie/RxScala,jbripley/RxScala,zjrstar/RxScala,hermanbanken/RxScala,TracyLu/RxScala,samuelgruetter/RxScala,hermanbanken/RxScala