Add support for Dynamic Entity Reference fields

vlad.dancer → made their first commit to this issue’s fork.

@Anybody, @Leon Kessler I applied patch and changed CorrespondingReferenceForm::getReferenceFieldMap to merge resulting array recursively:
array_merge_recursive($entity_reference_map, $dynamic_reference_map);
to prevent throwing away multiple references per one entity type.

I have ECK entity Person that includes two references: content reference (dynamic entity reference), user reference (default)
Here is example: https://monosnap.com/file/36HDVWg9e1s7fAhn32sTC2AQBA2cFQ

This doesn't apply cleanly to beta4. It applied to beta3, but applying https://www.drupal.org/project/cer/issues/2846318#comment-14841353 📌 Complete Synchronization functionality for existing reference values Needs work beforehand would also have it fail to apply.