Backup/Restore Managed Instance (#1428)

* Enabled backup to and restore from URL

* Created RPC, but when process tries to load Microsoft.Azure.Storage.Blob.dll, it crashes

* Added create shared access token

* Code refactor

* Minor changes

* Changed RPC path

* Moved createSas RPC to the newly created BlobService, fixed PR comments

* Added sas expiration date parameter to the RPC

* Added copyright headers

* Removed ConnectionInstance property from BlobService

* Removed unhelpful comment

* Removed unused using statements

* Changed copy/paste comments

* Disposable objects fix

* Small formatting fix

* Changed backup to/restore from url supported device types

* Added backup to url integration test

* Created restore integration test. Test are now getting azure blob params from env variables instead of file.

* Culture invariant epiration date param, fixed comment, and typo

* Updated headers

* PR comments fix

* Changed supported device type logic

* string localization fix

* String formatting fix

* build failure fix

* Typo

* Updated supported restore device types

test/Microsoft.SqlTools.ServiceLayer.Test.Common/AzureBlobConnectionSetting.cs

@@ -0,0 +1,17 @@
+//
+// 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.ServiceLayer.Test.Common
+{
+    public class AzureBlobConnectionSetting
+    {
+
+        public string BlobContainerUri { get; set; }
+
+        public string AccountKey { get; set; }
+
+        public string AccountName { get; set; }
+    }
+}