cubicweb #2719744 New RelationWidget (create a new entity) [rejected]

Add a relation widget allowing the creation of a new entity

prioritynormal
typeenhancement
done in<not specified>
load0.000
load left0.000
closed by<not specified>
patch'[web] create a new RelationWidget allowing to edit a new entity in a model dialog (closes #2719744)' [rejected]