Upgrade documentation and additional test

UPGRADE.md

+# Upgrade to 2.6
+
+## MINOR BC BREAK: URL-style DSN with percentage sign in password
+
+URL-style DSNs (e.g. ``mysql://foo@bar:localhost/db``) are now assumed to be percent-encoded
+in order to allow certain special characters in usernames, paswords and database names. If
+you are using a URL-style DSN and have a username, password or database name containing a
+percentage sign, you need to update your DSN. If your password is, say, ``foo%foo``, it
+should be encoded as ``foo%25foo``.
+
 # Upgrade to 2.5.1
 
 ## MINOR BC BREAK: Doctrine\DBAL\Schema\Table

tests/Doctrine/Tests/DBAL/DriverManagerTest.php

@@ -203,6 +203,10 @@ class DriverManagerTest extends \Doctrine\Tests\DbalTestCase
                 'mysql://foo%3A:bar%2F@localhost/baz+baz%40',
                 array('user' => 'foo:', 'password' => 'bar/', 'host' => 'localhost', 'dbname' => 'baz+baz@', 'driver' => 'Doctrine\DBAL\Driver\PDOMySQL\Driver'),
             ),
+            'simple URL with percent sign in password' => array(
+                'mysql://foo:bar%25bar@localhost/baz',
+                array('user' => 'foo', 'password' => 'bar%bar', 'host' => 'localhost', 'dbname' => 'baz', 'driver' => 'Doctrine\DBAL\Driver\PDOMySQL\Driver'),
+            ),
 
             // DBAL-1234
             'URL without scheme and without any driver information' => array(