fix typo

lib/preview/images.php

 <?php
 /**
  * Copyright (c) 2013 Frank Karlitschek frank@owncloud.org
- * Copyrigjt (c) 2013 Georg Ehrke georg@ownCloud.com
+ * Copyright (c) 2013 Georg Ehrke georg@ownCloud.com
  * This file is licensed under the Affero General Public License version 3 or
  * later.
  * See the COPYING-README file.

lib/preview/movies.php

 <?php
 /**
  * Copyright (c) 2013 Frank Karlitschek frank@owncloud.org
- * Copyrigjt (c) 2013 Georg Ehrke georg@ownCloud.com
+ * Copyright (c) 2013 Georg Ehrke georg@ownCloud.com
  * This file is licensed under the Affero General Public License version 3 or
  * later.
  * See the COPYING-README file.

lib/preview/mp3.php

 <?php
 /**
- * Copyrigjt (c) 2013 Georg Ehrke georg@ownCloud.com
+ * Copyright (c) 2013 Georg Ehrke georg@ownCloud.com
  * This file is licensed under the Affero General Public License version 3 or
  * later.
  * See the COPYING-README file.

lib/preview/pdf.php

 <?php
 /**
- * Copyrigjt (c) 2013 Georg Ehrke georg@ownCloud.com
+ * Copyright (c) 2013 Georg Ehrke georg@ownCloud.com
  * This file is licensed under the Affero General Public License version 3 or
  * later.
  * See the COPYING-README file.

lib/preview/unknown.php

 <?php
 /**
  * Copyright (c) 2013 Frank Karlitschek frank@owncloud.org
- * Copyrigjt (c) 2013 Georg Ehrke georg@ownCloud.com
+ * Copyright (c) 2013 Georg Ehrke georg@ownCloud.com
  * This file is licensed under the Affero General Public License version 3 or
  * later.
  * See the COPYING-README file.