Added builds against PHP nightly on Travis

According to the [documentation](https://docs.travis-ci.com/user/reference/trusty/#container-based-infrastructure), `sudo: false` is no longed needed since Trusty.

Backport PDO-related changes from master to 3.0.x

Use a wrapped PDO Statement instead of a custom class for `pdo_sqlsrv` since `PDOSqlsrv\Statement` doesn't extend `PDOStatement` anymore.

[DBAL-2958] Replaced extension of \PDOStatement with a composition to avoid having to replicate the \PDOStatement interface in ResultStatement

Remove superfluous Configuration instance

A configuration instance is not strictly required by [DriverManager::getConnection](https://github.com/doctrine/dbal/blob/master/lib/Doctrine/DBAL/DriverManager.php#L139).

As an upside, it doesn't add an extra warning for people that use Psalm/PHPmd when starting off from the documentation example. As the Configuration class has an `@internal` block those tools threat it as the other meaning for `@internal`, as in class that is [internal to the library and not for public use](https://docs.phpdoc.org/references/phpdoc/tags/internal.html).

Fix breaks named parameters in Oracle

[GH-3777] Don't remove composer lock travis on stable 2.10 branch

Allow build failures for unstable dependencies

Switched from PHPBrew-based configuration to the Docker-based

As per the support response, continuousphp switched to building their containers based on the official images from PHP.

Remove temporary SQLite file on teardown

Update deprecation messages to refer to DBAL