Fix themes and attachment icons.

Wino.Mail/App.xaml

@@ -17,6 +17,9 @@
                 <ResourceDictionary Source="Styles/ImagePreviewControl.xaml" />
 
                 <styles:WinoExpanderStyle />
+
+                <!--  Last item must always be the default theme.  -->
+                <ResourceDictionary Source="ms-appx:///Wino.Core.UWP/AppThemes/Mica.xaml" />
             </ResourceDictionary.MergedDictionaries>
         </ResourceDictionary>
     </Application.Resources>

Wino.Mail/AppShell.xaml

@@ -381,6 +381,7 @@
             x:Name="navigationView"
             Grid.Row="1"
             Grid.ColumnSpan="3"
+            Margin="-1,-1,0,0"
             HorizontalContentAlignment="Stretch"
             VerticalContentAlignment="Stretch"
             AlwaysShowHeader="True"

Wino.Mail/Views/MailListPage.xaml

@@ -228,7 +228,7 @@
         </Grid>
     </wino:BasePage.ShellContent>
 
-    <Grid x:Name="RootGrid">
+    <Grid x:Name="RootGrid" Padding="0,2,0,0">
         <Grid.ColumnDefinitions>
             <ColumnDefinition x:Name="MailListColumn" Width="{x:Bind ViewModel.MailListLength, Mode=OneWay, Converter={StaticResource GridLengthConverter}}" />
             <ColumnDefinition x:Name="RendererColumn" Width="*" />
@@ -506,6 +506,7 @@
 
             </Grid>
         </Border>
+        
         <toolkit:PropertySizer
             x:Name="MailListSizer"
             Grid.Column="1"
@@ -531,7 +532,8 @@
                 HorizontalAlignment="Center"
                 VerticalAlignment="Center"
                 Opacity="0.5"
-                Spacing="6">
+                Spacing="6"
+                Visibility="{x:Bind helpers:XamlHelpers.ReverseBoolToVisibilityConverter(ViewModel.ThemeService.IsCustomTheme)}">
 
                 <coreControls:WinoFontIcon FontSize="80" Icon="Mail" />