Find by label

```xaml
            <TextBlock Grid.Row="16"
                       Grid.Column="0"
                       Text="Min:" />
            <TextBox Grid.Row="16"
                     Grid.Column="1"
                     Text="{Binding Min, TargetNullValue=''}"  />
```

```cs
var textBox = window.FindTextBox("Min:")
```

Not sure if it should be `FindTextBoxByLabel()`