Enable file change tracking with Workspace and EditorSession.

Also include misc. clean-ups related to removing unneeded PowerShell Language Service code.

ServiceHost/Session/SqlToolsContext.cs

@@ -0,0 +1,25 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System;
+
+namespace Microsoft.SqlTools.EditorServices.Session
+{
+    public class SqlToolsContext
+    {
+        /// <summary>
+        /// Gets the PowerShell version of the current runspace.
+        /// </summary>
+        public Version SqlToolsVersion
+        {
+            get; private set;
+        }
+
+        public SqlToolsContext(HostDetails hostDetails, ProfilePaths profilePaths)
+        {
+            
+        }
+    }
+}