Add support to RxCocoa at Travis
Add support to RxCocoa at Travis

Carthage build.
RxSwiftCommunity/RxSwiftExt,tgyhlsb/RxSwiftExt,RxSwiftCommunity/RxSwift-Ext,RxSwiftCommunity/RxSwiftExt,RxSwiftCommunity/RxSwift-Ext,tgyhlsb/RxSwiftExt,RxSwiftCommunity/RxSwiftExt