Simple mvrx sample

mvrx_simple_sample.kt

data class HelloWorldState(val title: String = "Hello World") : MvRxState

class HelloWorldViewModel(initialState: HelloWorldState) : MyBaseMvRxViewModel<HelloWorldState>(initialState, debugMode = BuildConfig.DEBUG) {
    fun getMoreExcited() = setState { copy(title = "$title!") }
}

class HelloWorldFragment : BaseFragment() {
    private val viewModel: HelloWorldViewModel by fragmentViewModel()

    override fun EpoxyController.buildModels() = withState(viewModel) { state ->
        header {
            title(state.title)
        }
        basicRow { 
            onClick { viewModel.getMoreExcited() }
        }
    }
}