Added Perspex.Markup to NuGet package.

nuget/build-version.ps1

@@ -28,6 +28,8 @@ Copy-Item ..\src\Perspex.Styling\bin\Release\Perspex.Styling.dll $lib
 Copy-Item ..\src\Perspex.Styling\bin\Release\Perspex.Styling.xml $lib
 Copy-Item ..\src\Perspex.Themes.Default\bin\Release\Perspex.Themes.Default.dll $lib
 Copy-Item ..\src\Perspex.Themes.Default\bin\Release\Perspex.Themes.Default.xml $lib
+Copy-Item ..\src\Markup\Perspex.Markup\bin\Release\Perspex.Markup.dll $lib
+Copy-Item ..\src\Markup\Perspex.Markup\bin\Release\Perspex.Markup.xml $lib
 Copy-Item ..\src\Markup\Perspex.Markup.Xaml\bin\Release\Perspex.Markup.Xaml.dll $lib
 Copy-Item ..\src\Markup\Perspex.Markup.Xaml\bin\Release\Perspex.Markup.Xaml.xml $lib
 Copy-Item ..\src\Perspex.HtmlRenderer\bin\Release\Perspex.HtmlRenderer.dll $lib

src/Markup/Perspex.Markup/Perspex.Markup.csproj

@@ -32,6 +32,7 @@
     <DefineConstants>TRACE</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
+    <DocumentationFile>bin\Release\Perspex.Markup.XML</DocumentationFile>
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="Binding\ExpressionNodeBuilder.cs" />