RFE#919: Multiple-column foreign key relation.

Signed-off-by: Ashutosh Dhundhara <ashutoshdhundhara@yahoo.com>

Fix missing master column.

Signed-off-by: Ashutosh Dhundhara <ashutoshdhundhara@yahoo.com>

Fix failing test.

Signed-off-by: Ashutosh Dhundhara <ashutoshdhundhara@yahoo.com>

Fix coding styles.

Signed-off-by: Ashutosh Dhundhara <ashutoshdhundhara@yahoo.com>

Fix function doc.

Signed-off-by: Ashutosh Dhundhara <ashutoshdhundhara@yahoo.com>