Translations + bugfix

lib/providers/notifications_provider.dart

@@ -80,11 +80,11 @@ class DownloadNotification extends ObtainiumNotification {
   DownloadNotification(String appName, int progPercent)
       : super(
             appName.hashCode,
-            'Downloading $appName',
+            tr('downloadingX', args: [appName]),
             '',
             'APP_DOWNLOADING',
-            'Downloading App',
-            'Notifies the user of the progress in downloading an App',
+            tr('downloadingX', args: [tr('app')]),
+            tr('downloadNotifDescription'),
             Importance.low,
             onlyAlertOnce: true,
             progPercent: progPercent);

lib/providers/source_provider.dart

@@ -142,7 +142,7 @@ preStandardizeUrl(String url) {
   return url;
 }
 
-const String noAPKFound = 'No APK found';
+String noAPKFound = tr('noAPKFound');
 
 List<String> getLinksFromParsedHTML(
         Document dom, RegExp hrefPattern, String prependToLinks) =>
@@ -196,8 +196,7 @@ class AppSource {
     ],
     [
       GeneratedFormItem('noVersionDetection',
-          label: 'Do not attempt version detection', // TODO
-          type: FormItemType.bool)
+          label: tr('noVersionDetection'), type: FormItemType.bool)
     ]
   ];