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/ShowOnlineHelpRequest.cs

@@ -0,0 +1,16 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using Microsoft.SqlTools.EditorServices.Protocol.MessageProtocol;
+
+namespace Microsoft.SqlTools.EditorServices.Protocol.LanguageServer
+{
+    public class ShowOnlineHelpRequest
+    {
+        public static readonly 
+            RequestType<string, object> Type = 
+            RequestType<string, object>.Create("SqlTools/showOnlineHelp");
+    }
+}