Outdated Cartfile in MVVM-C project

[adamzarn]

I was getting an xcodebuild error when running carthage update --platform iOS for the MVVM-C project as it couldn't build RxDataSources. I got it to work by updating the cartfile to this:

github "ReactiveX/RxSwift" ~> 4.0.0
github "RxSwiftCommunity/RxDataSources" ~> 3.0

I don't want to create a PR because I'm not sure if this was just an issue for me.