Fixed: Added Various Missing Translations

cleanup en.json of unused translates

Fixes #1397

Closes Sonarr PR # 4791 'Fixed: Better wording of MissingFromDisk'

frontend/src/Activity/History/Details/HistoryDetails.js

@@ -215,13 +215,13 @@ function HistoryDetails(props) {
 
     switch (reason) {
       case 'Manual':
-        reasonMessage = 'File was deleted by via UI';
+        reasonMessage = translate('FileWasDeletedByViaUI');
         break;
       case 'MissingFromDisk':
-        reasonMessage = 'Readarr was unable to find the file on disk so it was removed';
+        reasonMessage = translate('MissingFromDisk');
         break;
       case 'Upgrade':
-        reasonMessage = 'File was deleted to import an upgrade';
+        reasonMessage = translate('FileWasDeletedByUpgrade');
         break;
       default:
         reasonMessage = '';

frontend/src/Activity/Queue/Queue.js

@@ -223,14 +223,14 @@ class Queue extends Component {
           {
             !isRefreshing && hasError &&
               <div>
-                Failed to load Queue
+                {translate('FailedToLoadQueue')}
               </div>
           }
 
           {
             isAllPopulated && !hasError && !items.length &&
               <div>
-                Queue is empty
+                {translate('QueueIsEmpty')}
               </div>
           }