Remove empty partial Extensions source file.

src/Renci.SshNet.WindowsPhone/Common/Extensions.WP.cs

@@ -1,9 +0,0 @@
-namespace Renci.SshNet.Common
-{
-    /// <summary>
-    /// Collection of different extension method specific for Windows Phone
-    /// </summary>
-    internal static partial class Extensions
-    {
-    }
-}

src/Renci.SshNet.WindowsPhone/Renci.SshNet.WindowsPhone.csproj

@@ -866,9 +866,6 @@
     <Compile Include="..\Renci.SshNet\SubsystemSession.cs">
       <Link>SubsystemSession.cs</Link>
     </Compile>
-    <Compile Include="Common\Extensions.WP.cs">
-      <SubType>Code</SubType>
-    </Compile>
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="..\Renci.SshNet\Properties\CommonAssemblyInfo.cs">
       <Link>Properties\CommonAssemblyInfo.cs</Link>

src/Renci.SshNet.WindowsPhone8/Renci.SshNet.WindowsPhone8.csproj

@@ -94,9 +94,6 @@
     <Compile Include="..\Renci.SshNet.Silverlight\Channels\ChannelDirectTcpip.SilverlightShared.cs">
       <Link>Channels\ChannelDirectTcpip.SilverlightShared.cs</Link>
     </Compile>
-    <Compile Include="..\Renci.SshNet.WindowsPhone\Common\Extensions.WP.cs">
-      <Link>Common\Extensions.WP.cs</Link>
-    </Compile>
     <Compile Include="..\Renci.SshNet\Abstractions\DnsAbstraction.cs">
       <Link>Abstractions\DnsAbstraction.cs</Link>
     </Compile>