Add third tier to key namespacing

- Changes all `app.trans` calls to `app.translator.trans` calls.
- Changes existing keys to [three-tier namespace structure](https://github.com/flarum/english/pull/12).
- Extracts additional strings for `lib:` namespace.
- Extracts two previously missed strings for EditGroupModal.js.

framework/core/js/lib/App.js

@@ -255,16 +255,16 @@ export default class App {
 
         case 401:
         case 403:
-          children = 'You do not have permission to do that.';
+          children = app.translator.trans('core.lib.error.permission_denied_message');
           break;
 
         case 404:
         case 410:
-          children = 'The requested resource was not found.';
+          children = app.translator.trans('core.lib.error.not_found_message');
           break;
 
         default:
-          children = 'Oops! Something went wrong. Please reload the page and try again.';
+          children = app.translator.trans('core.lib.error.generic_message');
       }
 
       error.alert = new Alert({

framework/core/js/lib/helpers/punctuateSeries.js

@@ -11,7 +11,7 @@
  */
 export default function punctuateSeries(items) {
   if (items.length === 2) {
-    return app.trans('core.lib.series_two_text', {
+    return app.translator.trans('core.lib.series.two_text', {
       first: items[0],
       second: items[1]
     });
@@ -21,10 +21,10 @@ export default function punctuateSeries(items) {
     // into the translator along with the first and last item.
     const second = items
       .slice(1, items.length - 1)
-      .reduce((list, item) => list.concat([item, app.trans('core.lib.series_glue_text')]), [])
+      .reduce((list, item) => list.concat([item, app.translator.trans('core.lib.series.glue_text')]), [])
       .slice(0, -1);
 
-    return app.trans('core.lib.series_three_text', {
+    return app.translator.trans('core.lib.series.three_text', {
       first: items[0],
       second,
       third: items[items.length - 1]

framework/core/js/lib/helpers/username.js

@@ -6,7 +6,7 @@
  * @return {Object}
  */
 export default function username(user) {
-  const name = (user && user.username()) || app.trans('core.forum.user_deleted_text');
+  const name = (user && user.username()) || app.translator.trans('core.lib.deleted_user_text');
 
   return <span className="username">{name}</span>;
 }

framework/core/js/lib/models/Discussion.js

@@ -86,7 +86,7 @@ Object.assign(Discussion.prototype, {
     const items = new ItemList();
 
     if (this.isHidden()) {
-      items.add('hidden', <Badge type="hidden" icon="trash" label="Hidden"/>);
+      items.add('hidden', <Badge type="hidden" icon="trash" label={app.translator.trans('core.lib.hidden_discussion_tooltip')}/>);
     }
 
     return items;

framework/core/js/lib/utils/abbreviateNumber.js

@@ -11,9 +11,9 @@
 export default function abbreviateNumber(number) {
   // TODO: translation
   if (number >= 1000000) {
-    return Math.floor(number / 1000000) + 'M';
+    return Math.floor(number / 1000000) + app.translator.trans('core.lib.number_suffix.mega_text');
   } else if (number >= 1000) {
-    return Math.floor(number / 1000) + 'K';
+    return Math.floor(number / 1000) + app.translator.trans('core.lib.number_suffix.kilo_text');
   } else {
     return number.toString();
   }