Unless otherwise noted, This software is in the public domain because it contains materials that originally came from the United States Geological Survey, an agency of the United States Department of Interior. For more information, see the official USGS copyright policy at http://www.usgs.gov/visual-id/credit_usgs.html#copyright
The file lib/classes/PdoSessionHandler.php is reused from the Symfony PHP Framework (https://github.com/symfony/symfony) and has a separate license; included in that file.