Data binding for Kotlin

On this example I used two-way data binding for Android

Sample implementation on XML:

<data>
   <variable name="user" type="br.com.kotlin.databinding.data.User"></variable>
</data>

<EditText
    android:id="@+id/txtUser"
    android:layout_width="0dp"
    android:layout_height="wrap_content"
    android:layout_marginEnd="16dp"
    android:layout_marginStart="16dp"
    android:layout_marginTop="16dp"
    android:text="@={user.name}"
    android:hint="@string/whats_your_name"
    app:layout_constraintHorizontal_bias="0.0"
    app:layout_constraintLeft_toLeftOf="parent"
    app:layout_constraintRight_toRightOf="parent"
    app:layout_constraintTop_toTopOf="parent" ></EditText>

Sample implementation on Kotlin object:

```kotlin
class User : BaseObservable(), Serializable {

companion object {
    fun build (name:String, nationality: String): User {
        val user = User()
        user.name = name
        user.nationality = nationality
        return user
    }
}
@Bindable
var name: String = String()
    set(value) {
        field = value
        notifyPropertyChanged(BR.name)
    }
    get() = field
@Bindable
var nationality: String = String()
    set(value) {
        field = value
        notifyPropertyChanged(BR.nationality)
    }
    get() = field

}