Issue 49928 - Refactor and improve schema CLI/lib389 part to DSLdapObject
Description: First commit that refactors Schema object and
removes SchemaLegacy usage from CLI.
Add full CLI Schema functionality to lib389.
It includes: list, query, add, edit, remove operations.
https://pagure.io/389-ds-base/issue/49928
Reviewed by: mreynolds, wibrown (Thanks!)