Add Import OPML functionality

iOS/Settings/SettingsImportSubscriptionsDocumentPickerView.swift

@@ -0,0 +1,52 @@
+//
+//  SettingsImportSubscriptionsDocumentPickerView.swift
+//  NetNewsWire-iOS
+//
+//  Created by Maurice Parker on 6/16/19.
+//  Copyright © 2019 Ranchero Software. All rights reserved.
+//
+
+import SwiftUI
+import Account
+
+struct SettingsImportSubscriptionsDocumentPickerView : UIViewControllerRepresentable {
+	var account: Account?
+	
+	func makeUIViewController(context: UIViewControllerRepresentableContext<SettingsImportSubscriptionsDocumentPickerView>) -> UIDocumentPickerViewController {
+		let docPicker = UIDocumentPickerViewController(documentTypes: ["public.xml", "org.opml.opml"], in: .import)
+		docPicker.delegate = context.coordinator
+		docPicker.modalPresentationStyle = .formSheet
+		return docPicker
+	}
+	
+	func updateUIViewController(_ uiViewController: UIDocumentPickerViewController, context: UIViewControllerRepresentableContext<SettingsImportSubscriptionsDocumentPickerView>) {
+		//
+	}
+	
+	func makeCoordinator() -> Coordinator {
+		return Coordinator(self)
+	}
+	
+	class Coordinator : NSObject, UIDocumentPickerDelegate {
+		var parent: SettingsImportSubscriptionsDocumentPickerView
+		
+		init(_ view: SettingsImportSubscriptionsDocumentPickerView) {
+			self.parent = view
+		}
+		
+		func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentsAt urls: [URL]) {
+			for url in urls {
+				parent.account?.importOPML(url) { result in}
+			}
+		}
+		
+	}
+}
+
+#if DEBUG
+struct SettingsImportSubscriptionsDocumentPickerView_Previews : PreviewProvider {
+    static var previews: some View {
+        SettingsImportSubscriptionsDocumentPickerView()
+    }
+}
+#endif