1. Change down version to list to accept multi verstion value 2. Update search function use BFS to find migration path 2. Add test case Signed-off-by: DQ <dengq@vmware.com>
The migration script should failure early when version is not supported Signed-off-by: DQ <dengq@vmware.com>
1. Refactor structure of migrate file 2. fix some previous bugs Signed-off-by: DQ <dengq@vmware.com>