title: libgit2sharp-ssh working with proxy?
body: <p>I use the <code>libgit2sharp-ssh</code> and i implement the ssh connection successfully but now the <code>https/http</code> connection is not working under proxy ? 
  i look at the implementation of the methods clone and Push in <code>libgit2sharp-ssh</code> lib and both of them the value of <code>ProxyOptions</code> is: </p>
  
  <pre><code>ProxyOptions = new GitProxyOptions { Version = 1 }  
  
     public virtual void Push(Remote remote, IEnumerable&lt;string&gt; pushRefSpecs, PushOptions pushOptions)
      {
          Ensure.ArgumentNotNull(remote, "remote");
          Ensure.ArgumentNotNull(pushRefSpecs, "pushRefSpecs");
  
          // Return early if there is nothing to push.
          if (!pushRefSpecs.Any())
          {
              return;
          }
  
          if (pushOptions == null)
          {
              pushOptions = new PushOptions();
          }
  
          // Load the remote.
          using (RemoteHandle remoteHandle = Proxy.git_remote_lookup(repository.Handle, remote.Name, true))
          {
              var callbacks = new RemoteCallbacks(pushOptions);
              GitRemoteCallbacks gitCallbacks = callbacks.GenerateCallbacks();
  
              Proxy.git_remote_push(remoteHandle,
                                    pushRefSpecs,
                                    new GitPushOptions()
                                    {
                                        PackbuilderDegreeOfParallelism = pushOptions.PackbuilderDegreeOfParallelism,
                                        RemoteCallbacks = gitCallbacks,
                                        ProxyOptions = new GitProxyOptions { Version = 1 },
                                    });
          }
      }
  
  
  internal enum GitProxyType
  {
      None,
      Auto,
      Specified
  }
  
  [StructLayout(LayoutKind.Sequential)]
  internal struct GitProxyOptions
  {
      public uint Version;
      public GitProxyType Type;
      public IntPtr Url;
      public IntPtr CredentialsCb;
      public IntPtr CertificateCheck;
      public IntPtr CbPayload;
  }
  </code></pre>
  
  <p>}</p>
  
  <p>is <code>libgit2sharp-ssh</code> not support working with proxy when using the <code>http/s</code> connection to git ?? (because working with libgit2sharp without the implementation of the ssh work with proxy well ) </p>