Create a FieldTrait to gather a list of fields for commands

[cosmicdreams]

Last night on Drupal and Coffee we started making a FieldTrait that would gather up all the fields from a Drupal site so that we could have a wizard pick one and then pass that info to some kind of field generator.

Kind of like FormTrait and the Form Generator.

I think it would be really impressive if we could leverage a FieldTrait to create a command where you generate a content type / custom entity / thingy and then generate all the fields that should be associated with it.

A common frustration during the content modeling part of a project is having to click through all the pages for fields. If we had a command that did this then we'd be able to make all the decisions for the fields up front and then batch all the config generation.