Add a convenience link to Syntax.xml into CSharpSyntaxGenerator.csproj

src/Tools/Source/CompilerGeneratorTools/Source/CSharpSyntaxGenerator/CSharpSyntaxGenerator.csproj

-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 <!-- Copyright (c)  Microsoft.  All Rights Reserved.  Licensed under the Apache License, Version 2.0.  See License.txt in the project root for license information. -->
 <Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <ImportGroup Label="Settings">
@@ -44,6 +44,11 @@
   <ItemGroup>
     <None Include="project.json" />
   </ItemGroup>
+  <ItemGroup>
+    <Content Include="..\..\..\..\..\Compilers\CSharp\Portable\Syntax\Syntax.xml">
+      <Link>Syntax.xml</Link>
+    </Content>
+  </ItemGroup>
   <ImportGroup Label="Targets">
     <Import Project="..\..\..\..\..\..\build\Targets\VSL.Imports.targets" />
   </ImportGroup>