Support for database drivers

Migrated issue

Reported by: bohart

Drupal 8 core has hardcoded path of database drivers folders in drupal_get_database_types.
That means all database drivers should be installed in DRUPAL_ROOT . '/drivers/lib/Drupal/Driver/Database/ folder.

Currently, drupal.org packagist return package type `drupal-module` for all contrib modules.
That means composer installer-paths can't determine the difference between modules and database drivers.

It looks like we should allowing having "type": "drupal-database-driver" in modules composer.json files, isn't it?

Here is an example driver with workinf Drupal8:
https://www.drupal.org/project/oracle