Fix PDO::inTransaction() test for pgsql

inTransaction() nowadays casts the in_transaction result to boolean.
I'm not sure whether the INERROR state should result in true or false.
For now I went with the result that we actually get.
Improved test portability so that it doesn't fail with pdo_pgsql
Clean up leftover test files
Merge branch 'PHP-5.3' into PHP-5.4

* PHP-5.3:
  Clean up leftover test files