Updated Books.php

This change has been generated by a script that has detected changes in the
discovery doc of the API.

Check http://developers.google.com/discovery for more info.

Author: silvolu

src/Google/Service/Books.php

@@ -1834,8 +1834,9 @@ public function syncVolumeLicenses($source, $nonce, $cpksver, $optParams = array
   }
 
   /**
-   * Sets the settings for the user. Unspecified sub-objects will retain the
-   * existing value. (myconfig.updateUserSettings)
+   * Sets the settings for the user. If a sub-object is specified, it will
+   * overwrite the existing sub-object stored in the server. Unspecified sub-
+   * objects will retain the existing value. (myconfig.updateUserSettings)
    *
    * @param Google_Usersettings $postBody
    * @param array $optParams Optional parameters.
@@ -6092,6 +6093,7 @@ class Google_Service_Books_VolumeVolumeInfo extends Google_Collection
   public $infoLink;
   public $language;
   public $mainCategory;
+  public $maturityRating;
   public $pageCount;
   public $previewLink;
   public $printType;
@@ -6201,6 +6203,14 @@ public function getMainCategory()
   {
     return $this->mainCategory;
   }
+  public function setMaturityRating($maturityRating)
+  {
+    $this->maturityRating = $maturityRating;
+  }
+  public function getMaturityRating()
+  {
+    return $this->maturityRating;
+  }
   public function setPageCount($pageCount)
   {
     $this->pageCount = $pageCount;