[iOS] launch image for iPhoneX

Xamarin.Forms.ControlGallery.iOS/Info.plist

@@ -33,6 +33,7 @@
 	<array>
 		<string>Default@2x.png</string>
 		<string>Default-568h@2x.png</string>
+		<string>Default-812h@3x.png</string>
 	</array>
 	<key>UIViewControllerBasedStatusBarAppearance</key>
 	<true/>
@@ -44,6 +45,16 @@
 	<string></string>
 	<key>UILaunchImages</key>
 	<array>
+		<dict>
+			<key>UILaunchImageMinimumOSVersion</key>
+			<string>11.0</string>
+			<key>UILaunchImageName</key>
+			<string>Default-812h</string>
+			<key>UILaunchImageOrientation</key>
+			<string>Portrait</string>
+			<key>UILaunchImageSize</key>
+			<string>{375, 812}</string>
+		</dict>
 		<dict>
 			<key>UILaunchImageMinimumOSVersion</key>
 			<string>8.0</string>

Xamarin.Forms.ControlGallery.iOS/Xamarin.Forms.ControlGallery.iOS.csproj

@@ -294,6 +294,7 @@
     <BundleResource Include="Resources\twitternav%402x.png" />
     <BundleResource Include="Resources\xamarinlogo.png" />
     <BundleResource Include="coffee.png" />
+    <Content Include="Default-812h%403x.png" />
   </ItemGroup>
   <ItemGroup>
     <Reference Include="AdvancedColorPicker, Version=2.0.0.0, Culture=neutral, processorArchitecture=MSIL">