Possibility to choose whether generate a json or a yaml file with the CLI command

[benjdl]

Hello & thanks for your package!

The CLI command doesn't let the possibility to generate a json file instead of a yaml file, although a method toJson() exists in the source code.
Do you think this can be added in the next release ?

[d4nyll]

Thank you for the suggestion! I agree it should be added to the CLI, so I will try to add the feature the next time I'm on the plane 🛫