VERY PRELIMINARY support for PostgreSQL and IBM db2

...ers/slapd/back-sql/rdbms_depend/ibmdb2/backsql_create.sql

servers/slapd/back-sql/rdbms_depend/ibmdb2/backsql_drop.sql

servers/slapd/back-sql/rdbms_depend/ibmdb2/slapd.conf

servers/slapd/back-sql/rdbms_depend/ibmdb2/testdb_create.sql

servers/slapd/back-sql/rdbms_depend/ibmdb2/testdb_data.sql

servers/slapd/back-sql/rdbms_depend/ibmdb2/testdb_drop.sql

...rs/slapd/back-sql/rdbms_depend/ibmdb2/testdb_metadata.sql

servers/slapd/back-sql/rdbms_depend/pgsql/backsql_create.sql

servers/slapd/back-sql/rdbms_depend/pgsql/backsql_drop.sql

servers/slapd/back-sql/rdbms_depend/pgsql/slapd.conf

servers/slapd/back-sql/rdbms_depend/pgsql/testdb_create.sql

servers/slapd/back-sql/rdbms_depend/pgsql/testdb_data.sql

servers/slapd/back-sql/rdbms_depend/pgsql/testdb_drop.sql

...ers/slapd/back-sql/rdbms_depend/pgsql/testdb_metadata.sql