#40: Use the Rust AuthenticationService.

* Update SDK package to 1.0.12-alpha.
* Use an app group for storage and stop stripping the http from the homeserver when configuring the service.
* Rename access token to restore token.
* Remove matrix.org server description inline with latest FTUE changes.

ElementX/Sources/Services/UserSessionStore/FileManager.swift

@@ -0,0 +1,16 @@
+//
+//  FileManager.swift
+//  ElementX
+//
+//  Created by Doug on 19/07/2022.
+//  Copyright © 2022 Element. All rights reserved.
+//
+
+import Foundation
+
+extension FileManager {
+    /// The URL of the primary app group container.
+    var appGroupContainerURL: URL? {
+        containerURL(forSecurityApplicationGroupIdentifier: ElementInfoPlist.appGroupIdentifier)
+    }
+}