[CLI] Take input for npm package name in all CLI generators with a default behaviour

Nadie ha tomado este issue todavía.

## Feature proposal
Allow users to enter a npm package name for app and extensions. While they can still go change in package.json, there remains a doubt in user's mind if all required changes are done to change the package name. We can show a default suggestion based on the application or extension name after checking for valid package name. For a custom entered name, we still need to check for name validity.

## Current Behavior

Currently npm package name is auto generated based on the project name. This holds for both extensions and app.

## Expected Behavior

An extra option should come in CLI asking for a package name where users can choose to provide their scoped package names or any other name they want. Generator checks for the validity and shows a message if the package name is invalid. If everything is fine, it uses the provided name for npm package name.

Comienza localizando el código del generador de CLI que actualmente deriva los nombres de los paquetes y compara después los flujos del generador de apps y del generador de extensiones. La tarea estará terminada cuando ambos flujos soliciten un nombre de paquete opcional, sugieran un valor predeterminado válido, validen la entrada personalizada y usen el nombre aceptado en package.json.

Escrito por el modelo de indexación a partir del texto del issue.