Add description of the MVVM elements ot the corresponding classes. Also some doc for methods

enzevalos_iphone/AuthenticationModel.swift

@@ -9,6 +9,9 @@
 import Foundation
 import Combine
 
+/**
+ Model of the Authentication according to MVVP pattern. Performs all the necessary server calls according to the data provided by the ViewModel
+ */
 class AuthenticationModel: NSObject {
     
     enum AuthenticationResult {case Success, Timeout, Error(value: MailServerConnectionError)}
@@ -29,6 +32,12 @@ class AuthenticationModel: NSObject {
         
     /**
      Start asynchronous tasks for checking IMAP and SMTP configuration with a *timeoutDelay* after which the tasks are not getting consumed anymore.
+     
+     - Parameters:
+        - mailAccount: data class that holds the properties used for establishing the connection
+        - extendedValidation: indicates whether the imap/smtp configuration got specified by the user or should use default values
+     
+     -  Returns: a Future that produces an AuthenticationResult once the server calls are done
      */
     func checkConfig(mailAccount: MailAccount, extendedValidation: Bool) -> Future<AuthenticationResult, Never> {
         self.extendedValidation = extendedValidation
@@ -152,9 +161,11 @@ class AuthenticationModel: NSObject {
             smtpConfigurationSuccessful = false
         }
         dispatchGroup.leave()
-        return
     }
     
+    /**
+     A listner class that notifies the AuthenticationCallback's about the result once the server call is done
+     */
     class Listener: MailSessionListener {
         let callback: AuthenticationCallback
         let mailAccount: MailAccount

enzevalos_iphone/AuthenticationScreen.swift

@@ -8,6 +8,9 @@
 
 import SwiftUI
 
+/**
+ View of the Authentication according to MVVP pattern. Observes the AuthenticationViewModel and adjusts the displayed data accordingly
+ */
 struct AuthenticationScreen: View {
     @State private var login: String = ""
     @State private var password: String = ""

enzevalos_iphone/AuthenticationViewModel.swift

@@ -9,6 +9,9 @@
 import Foundation
 import Combine
 
+/**
+ ViewModel of the Authentication according to MVVP pattern. Uses AuthenticationModel to get the result of the authentication.
+ */
 class AuthenticationViewModel : ObservableObject {
 
     @Published var errorMessage: String?