removed unused interface

Author: retailcoder

RetailCoder.VBE/Rubberduck.csproj

@@ -896,7 +896,6 @@
     <Compile Include="UI\Splash.Designer.cs">
       <DependentUpon>Splash.cs</DependentUpon>
     </Compile>
-    <Compile Include="UI\ToDoItems\IToDoExplorerWindow.cs" />
     <Compile Include="Settings\IConfigurationService.cs" />
     <Compile Include="Settings\ConfigurationLoader.cs" />
     <Compile Include="Settings\UserSettings.cs" />