Removing project change

Author: StanleyGoldman

src/UnityExtension/Assets/Editor/GitHub.Unity/GitHub.Unity.csproj

@@ -87,7 +87,6 @@
     <Compile Include="EntryPoint.cs" />
     <Compile Include="Misc\Installer.cs" />
     <Compile Include="UI\BaseWindow.cs" />
-    <Compile Include="UI\ChangesTreeControl.cs" />
     <Compile Include="UI\PopupWindow.cs" />
     <Compile Include="UI\ProjectWindowInterface.cs" />
     <Compile Include="Misc\Styles.cs" />