Move unused forked code to external directory (#1192)

* Move unused forked code to external directory

* Fix SLN build errors

* Add back resource provider core since it's referenced by main resource provider project

* Update PackageProjects step of pipeline

external/Microsoft.SqlTools.CoreServices/Connection/ReliableConnection/Resources.cs

@@ -0,0 +1,157 @@
+//
+// 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.Connection.ReliableConnection
+{
+    /// <summary>
+    /// Contains string resources used throughout ReliableConnection code.
+    /// </summary>
+    internal static class Resources
+    {
+        internal static string AmbientSettingFormat
+        {
+            get
+            {
+                return "{0}: {1}";
+            }
+        }
+
+        internal static string ConnectionPassedToIsCloudShouldBeOpen
+        {
+            get
+            {
+                return "connection passed to IsCloud should be open.";
+            }
+        }
+
+        internal static string ConnectionPropertyNotSet
+        {
+            get
+            {
+                return "Connection property has not been initialized.";
+            }
+        }
+
+        internal static string ExceptionCannotBeRetried
+        {
+            get
+            {
+                return "Exception cannot be retried because of err #{0}:{1}";
+            }
+        }
+
+        internal static string ErrorParsingConnectionString
+        {
+            get
+            {
+                return "Error parsing connection string {0}";
+            }
+        }
+
+        internal static string FailedToCacheIsCloud
+        {
+            get
+            {
+                return "failed to cache the server property of IsAzure";
+            }
+        }
+
+        internal static string FailedToParseConnectionString
+        {
+            get
+            {
+                return "failed to parse the provided connection string: {0}";
+            }
+        }
+
+        internal static string IgnoreOnException
+        {
+            get
+            {
+                return "Retry number {0}. Ignoring Exception: {1}";
+            }
+        }
+
+        internal static string InvalidCommandType
+        {
+            get
+            {
+                return "Unsupported command object.  Use SqlCommand or ReliableSqlCommand.";
+            }
+        }
+
+        internal static string InvalidConnectionType
+        {
+            get
+            {
+                return "Unsupported connection object.  Use SqlConnection or ReliableSqlConnection.";
+            }
+        }
+
+        internal static string LoggingAmbientSettings
+        {
+            get
+            {
+                return "Logging Ambient Settings...";
+            }
+        }
+
+        internal static string Mode
+        {
+            get
+            {
+                return "Mode";
+            }
+        }
+
+        internal static string OnlyReliableConnectionSupported
+        {
+            get
+            {
+                return "Connection property can only be set to a value of type ReliableSqlConnection.";
+            }
+        }
+
+        internal static string RetryOnException
+        {
+            get
+            {
+                return "Retry number {0}. Delaying {1} ms before next retry. Exception: {2}";
+            }
+        }
+
+        internal static string ThrottlingTypeInfo
+        {
+            get
+            {
+                return "ThrottlingTypeInfo";
+            }
+        }
+
+        internal static string UnableToAssignValue
+        {
+            get
+            {
+                return "Unable to assign the value of type {0} to {1}";
+            }
+        }
+
+        internal static string UnableToRetrieveAzureSessionId
+        {
+            get
+            {
+                return "Unable to retrieve Azure session-id.";
+            }
+        }
+
+        internal static string ServerInfoCacheMiss
+        {
+            get
+            {
+                return "Server Info does not have the requested property in the cache";
+            }
+        }
+    }
+}