Import ECC entity in YAML format on the fly.

We need a functionality to import ECC entity. Accessible format is YAML.

There should a separate action "Import ECC" next to "Add ECC".

By leading the import page there should be only one textarea field to paste YAML configuration of your ECC entity.

There should be validation by machine name, if the entity exists with the same machine name we will need to show a confirm page to update existing entity

Otherwise create a new entity based on YAML configuration.