Select field widget from field definition form

[Martronic-SA]

Following this community tread, there shoud be a simple way for the end user to select the widget he wants for a field directly from the field form when declaring a dexterity content type (avoid going to the ZMI to add this manually in the schema definition).
This would improve greatly the user exprience.

For example display a Multi selection field as checkbox, a simple selection as radio. The same for a simple relation or multi relation field.