Issue 49928 - WebUI schema functionality and improve CLI part
Description: Add schema functionality for add/edit/remove for
for attributes and objectClasses. Add get_attr_syntaxes funciton.
Fix small CLI schema issues and lib389 API part.
Set LogCapture level on the init.
Add copyright for cli/conf_backup_test.py.
https://pagure.io/389-ds-base/issue/49928
Reviewed by: mreynolds, mhonek (Thanks!)