Após incluir os codigos para o relacionamento entre as tabelas ( aula Relacionamento e Migrações) executei o comando "Add-Migration Modelo" mas o sistema apresentou o seguinte erro:
The child/dependent side could not be determined for the one-to-one relationship between 'Pedido.Cadastro' and 'Cadastro.Pedido'. To identify the child/dependent side of the relationship, configure the foreign key property. If these navigations should not be part of the same relationship configure them without specifying the inverse. See http://go.microsoft.com/fwlink/?LinkId=724062 for more details.