Merge ServiceHost xUnit test project into dev. (#5)

* Setup standard src, test folder structure.  Add unit test project.

* Actually stage the deletes.  Update .gitignore

src/ServiceHost/LanguageServer/ClientCapabilities.cs

@@ -0,0 +1,18 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+
+namespace Microsoft.SqlTools.EditorServices.Protocol.LanguageServer
+{
+    /// <summary>
+    /// Defines a class that describes the capabilities of a language
+    /// client.  At this time no specific capabilities are listed for
+    /// clients.
+    /// </summary>
+    public class ClientCapabilities
+    {
+    }
+}
+