Resolves: bug 345711
    Bug Description: migration : ignore idl switch value in 6.21 and earlier
    Reviewed by: nhosoi (Thanks!)
    Fix Description: If we are migrating a 6.21 or older database, we must not preserve the old idl switch setting, we must use the new default.  We also have to use LDIF files for database migration as we cannot reuse the old binary database files.
    Platforms tested: RHEL5 x86_64
    Flag Day: no
    Doc impact: no
    QA impact: should be covered by regular nightly and manual testing
    New Tests integrated into TET: none