use simplified progress wording as after first user testing on android

deltachat-ios/Controller/AccountSetup/WelcomeViewController.swift

@@ -329,15 +329,13 @@ class WelcomeViewController: UIViewController, ProgressAlertHandler {
                 } else {
                     guard let permille = ui["progress"] as? Int else { return }
                     var statusLineText = ""
-                    if permille <= 50 {
-                        statusLineText = "Receiving collection..."
-                    } else if permille <= 100 {
-                        statusLineText = "Collection received."
+                    if permille <= 100 {
+                        statusLineText = String.localized("preparing_account")
                     } else if permille <= 950 {
                         let percent = ((permille-100)*100)/850
-                        statusLineText = "Transfer... \(percent)%"
+                        statusLineText = String.localized("transferring") + " \(percent)%"
                     } else {
-                        statusLineText = "Finishing..."
+                        statusLineText = "Finishing..." // range not used, should not happen
                     }
                     self.updateProgressAlert(message: statusLineText)
                 }

deltachat-ios/Controller/BackupTransferViewController.swift

@@ -111,12 +111,8 @@ class BackupTransferViewController: UIViewController {
                     self.transferState = TranferState.error
                     self.showLastErrorAlert("Error")
                     hideQrCode = true
-                } else if permille <= 100 {
-                    statusLineText = String.localized("exporting_account")
-                } else if permille <= 300 {
-                    statusLineText = String.localized("preparing_account")
                 } else if permille <= 350 {
-                    statusLineText = String.localized("account_prepared")
+                    statusLineText = String.localized("preparing_account")
                 } else if permille <= 400 {
                     statusLineText = String.localized("waiting_for_receiver")
                 } else if permille <= 450 {
@@ -124,7 +120,7 @@ class BackupTransferViewController: UIViewController {
                     hideQrCode = true
                 } else if permille < 1000 {
                     let percent = (permille-450)/5
-                    statusLineText = String.localized("transferring") + " \(percent)%"
+                    statusLineText = String.localized("transferring") + " \(percent)%" // TODO: use a scrollbar, show precide percentage only for receiver
                     hideQrCode = true
                 } else if permille == 1000 {
                     self.transferState = TranferState.success