Allow horizontal scrolling, either move the command/proc column to the right or separate the two

Describe the feature request

What is the feature of interest? Be clear and concise.

Would tackle the issue raised in https://github.com/ClementTsang/bottom/issues/432.

What I'm thinking is to add key to toggle between the current mode which tries to fit everything, and one that allows scrolling and expands everything to full size.