Consider changing clone handlers to use core's entity duplication API

Problem/Motivation

Was any consideration given to using the built in entity duplication API in core.

E.g. http://cgit.drupalcode.org/entity_clone/tree/src/EntityClone/Content/Con...

Could just do this

$cloned_entity = $cloned_entity->createDuplicate();
$cloned_entity->save();

There is a fair bit of logic in ::createDuplicate that isn't covered by this module

Contrib modules have their own implementations - e.g. paragraphs http://cgit.drupalcode.org/paragraphs/tree/src/Entity/Paragraph.php?h=8....

Proposed resolution

Remaining tasks

User interface changes

API changes

Data model changes