Allow the user to customise the columns displayed in `py list`

Is your feature request related to a problem? Please describe.
I don't find the default display of py list particularly useful. The aliases take up a lot of space and aren't very helpful (they are easily deducible from the rest of the data). Ideally, I'd like to be able to choose more useful information to display in place of that column.

Describe the solution you'd like
The --format option allows you to display a single data item (--format=exe). That's fine, but it would be nice to be able to choose multiple values. Something like --format=tag,exe.

Describe alternatives you've considered
You can get this sort of report by piping --format=json into jq, or into a custom formatter, but that's fairly clumsy.

Additional context
Alternative to #86. The approach here is probably overkill, but I've filed it as an option in case changing the default format is unacceptable.

Comienza localizando el manejo de --format del comando py list y compara su salida para un solo elemento con la salida JSON existente. Define cómo deben analizarse y representarse los valores separados por comas, como tag,exe, y luego verifica que varios campos seleccionados aparezcan en el orden solicitado sin modificar el comportamiento existente para un único valor.