THRIFT-1742 Optionally implement hashcode and equals in c#

Patch: Carl Yeksigian
diff --git a/lib/csharp/src/Thrift.csproj b/lib/csharp/src/Thrift.csproj
index 0263d72..0722c18 100644
--- a/lib/csharp/src/Thrift.csproj
+++ b/lib/csharp/src/Thrift.csproj
@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>

+<?xml version="1.0" encoding="utf-8"?>

 <!--

   Licensed to the Apache Software Foundation (ASF) under one

   or more contributor license agreements. See the NOTICE file

@@ -77,6 +77,7 @@
     <Reference Include="System.Web" />

   </ItemGroup>

   <ItemGroup>

+    <Compile Include="Collections\TCollections.cs" />

     <Compile Include="Collections\THashSet.cs" />

     <Compile Include="Properties\AssemblyInfo.cs" />

     <Compile Include="Protocol\TAbstractBase.cs" />

@@ -137,4 +138,4 @@
   <ProjectExtensions>

     <VisualStudio AllowExistingFolder="true" />

   </ProjectExtensions>

-</Project>
\ No newline at end of file
+</Project>