Feature suggestion - change model

[leoalho]

Hi! First of all thank you for making this nice and lightweight piece of tech!
I am occasionally faced with the need to change the current model. Instead of closing and running the script with a new -m parameter it would be nice to have its own command for it. I created a PR, #152, which adds a change_model: command. I have tested that it works as intended

Best regards,
Leo Alho