feature request: infinite scrollback

[FStefanni]

Hi,

as the title suggest, this is a feature request: it would be nice to have a infinite scrollback functionality, so that as long as I do not close the terminal, I can check the previous output.

This is useful when running commands which creates a lot of logs in the terminal, which happens to me since i use the terminal
to inspect the status of the container running nodered in case of issues (so I use it to run diagnostic commands).

For example, a negative value in the "scrollback" option could mean "infinite".

Regards