Fix driver exception conversion for newer SQLite versions

As of [PHP 5.5.11](http://www.php.net/ChangeLog-5.php#5.5.11) the internal `libsqlite` has been upgraded to version `3.8.3.1` which seems to change some of the driver exception messages for constraint violations and causes [Travis to fail](https://travis-ci.org/doctrine/dbal/jobs/24234077#L187).
This PR now also matches strings to catch those appropriately.