message: Fix 'Login/Signup switch link' section layout
diff: Width="300" Height="460"
  Background="{DynamicResource Toggl.CardBackground}"
  VerticalAlignment="Center" HorizontalAlignment="Center">
  - <StackPanel>
  + <DockPanel>
  <Image Source="{DynamicResource Toggl.LogoImage}"
  + DockPanel.Dock="Top"
  Margin="0 50 0 0"
  SnapsToDevicePixels="True"
  Stretch="None" />
  + <StackPanel Orientation="Vertical"
  + DockPanel.Dock="Bottom"
  + Margin="0 44 0 0">
  + <TextBlock Text="Don't have an account?"
  + Style="{DynamicResource Toggl.CaptionBlackText}"
  + HorizontalAlignment="Center"
  + Visibility="{Binding SelectedConfirmAction, Converter={StaticResource ShowOnLogIn}}"/>
  +
  + <Label HorizontalAlignment="Center"
  + Margin="0 1 0 24">
  + <Hyperlink Style="{StaticResource Toggl.NormalHyperlink}"
  + Click="onSignupLoginToggleClick">
  + <Hyperlink.Inlines>
  + <Run Text="{Binding SignupLoginToggleText, Mode=OneWay}" />
  + </Hyperlink.Inlines>
  + </Hyperlink>
  + </Label>
  + </StackPanel>
  <StackPanel x:Name="formPanel" x:FieldModifier="private">
  <TextBox x:Name="emailTextBox" x:FieldModifier="private"
  Margin="0 20 0 0"
  VerticalAlignment="Center"/>
  </StackPanel>
  </Button>
  -
  - <TextBlock Text="Don't have an account?"
  - Margin="0 82 0 0"
  - Style="{DynamicResource Toggl.CaptionBlackText}"
  - HorizontalAlignment="Center"
  - Visibility="{Binding SelectedConfirmAction, Converter={StaticResource ShowOnLogIn}}"/>
  - <!-- TODO: when implementing new validation UI, make it DockPanel.Dock="Bottom" with a Bottom margin instead -->
  -
  - <Label HorizontalAlignment="Center"
  - Margin="0 1 0 24">
  - <Hyperlink Style="{StaticResource Toggl.NormalHyperlink}"
  - Click="onSignupLoginToggleClick">
  - <Hyperlink.Inlines>
  - <Run Text="{Binding SignupLoginToggleText, Mode=OneWay}" />
  - </Hyperlink.Inlines>
  - </Hyperlink>
  - </Label>
  - </StackPanel>
  </StackPanel>
  + </DockPanel>
  </Border>
  </Grid>
  </UserControl>
  