Demonstrates that NULL parameters are handled incorrectly by the sql parser utils as of 2.3.4

If allow_url_fopen isnt enabled, fopen will return false.

Fixed a PHP warning in DBALException::driverExceptionDuringQuery() when a parameter contains binary data.

- added test for getListTableColumnsSQL
- added test for getListTableForeignKeysSQL
- added test for getListTableIndexesSQL

This reverts commit d7032199.

DBAL-54 was fixed in commit 3d55dc8e by
changing SQL queries order. However it was later reintroduced.

This patch uses a different, more future-proof way, approach by using
DROP SEQUENCE ... CASCADE syntax, and thus does not depend on queries order.

fix :: operator in sql parser