VS Add-in more properties and improvements

visual_studio/NativeClientVSAddIn/NaCl.Build.CPPTasks/NaCl.Build.CPPTasks.csproj

 <?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup>
     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
     <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
     <ProductVersion>8.0.30703</ProductVersion>
     <SchemaVersion>2.0</SchemaVersion>
     <ProjectGuid>{FCD6F8FE-DF89-4232-A138-42C97826712A}</ProjectGuid>
     <OutputType>Library</OutputType>
     <AppDesignerFolder>Properties</AppDesignerFolder>
@@ skipping 20 matching lines @@
     <DefineConstants>TRACE</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
     <WarningLevel>4</WarningLevel>
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="Microsoft.Build" />
     <Reference Include="Microsoft.Build.CPPTasks.Common, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL" />
     <Reference Include="Microsoft.Build.Framework" />
     <Reference Include="Microsoft.Build.Tasks.v4.0" />
     <Reference Include="Microsoft.Build.Utilities.v4.0" />
+    <Reference Include="Microsoft.VisualStudio.Shell.10.0, Version=10.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a, processorArchitecture=MSIL" />
     <Reference Include="System" />
     <Reference Include="System.Core" />
     <Reference Include="System.Management" />
     <Reference Include="System.Windows.Forms" />
     <Reference Include="System.Xaml" />
     <Reference Include="System.Xml.Linq" />
     <Reference Include="System.Data.DataSetExtensions" />
     <Reference Include="Microsoft.CSharp" />
     <Reference Include="System.Data" />
     <Reference Include="System.Xml" />
@@ skipping 27 matching lines @@
     </PostBuildEvent>
   </PropertyGroup>
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
   <Target Name="BeforeBuild">
   </Target>
   <Target Name="AfterBuild">
   </Target>
   -->
 </Project>