Add v2 of the Hosting Service and build nuget packages for it (#675)

* Port v2 of Hosting service to SqlToolsService
- Renamed project to .v2 so that existing hosted service isn't impacted
- Copied over the CoreServices project which contains ConnectionServiceCore and other reusable services for anything interacting with MSSQL
- Ported unit test project across and verified tests run.

* Nuget package support for reusable DLLs

* Use 1.1 version per Karl's suggestion

* Use correct license URL and project URL

* Use new SMO packages

src/Microsoft.SqlTools.CoreServices/SqlContext/ObjectExplorerSettings.cs

@@ -0,0 +1,32 @@
+//
+// 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.CoreServices.SqlContext
+{
+    /// <summary>
+    /// Contract for receiving object explorer settings as part of workspace settings
+    /// </summary>
+    public class ObjectExplorerSettings
+    {
+        public static int DefaultCreateSessionTimeout = 45;
+        public static int DefaultExpandTimeout = 45;
+
+        public ObjectExplorerSettings()
+        {
+            CreateSessionTimeout = DefaultCreateSessionTimeout;
+            ExpandTimeout = DefaultExpandTimeout;
+        }
+
+        /// <summary>
+        /// Number of seconds to wait before fail create session request with timeout error
+        /// </summary>
+        public int CreateSessionTimeout { get; set; }
+
+        /// <summary>
+        /// Number of seconds to wait before fail expand request with timeout error
+        /// </summary>
+        public int ExpandTimeout { get; set; }
+    }
+}