Add content hub and a11y changes from Drupal git

See Drupal 7 git for git history for these commits.

Author: thomasmars

fonts/h5p-core-26.eot

@@ -9,6 +9,10 @@ abstract class H5PMetadata {
       'type' => 'text',
       'maxLength' => 255
     ),
+    'a11yTitle' => array(
+      'type' => 'text',
+      'maxLength' => 255,
+    ),
     'authors' => array(
       'type' => 'json'
     ),
@@ -57,6 +61,7 @@ public static function toJSON($content) {
     // Note: deliberatly creating JSON string "manually" to improve performance
     return
       '{"title":' . (isset($content->title) ? json_encode($content->title) : 'null') .
+      ',"a11yTitle":' . (isset($content->a11y_title) ? $content->a11y_title : 'null') .
       ',"authors":' . (isset($content->authors) ? $content->authors : 'null') .
       ',"source":' . (isset($content->source) ? '"' . $content->source . '"' : 'null') .
       ',"license":' . (isset($content->license) ? '"' . $content->license . '"' : 'null') .