Use Rich for the CLI console output

[choldgraf]

Description

Rich is a Python CLI output tool for rendering more feature-full console output. I think it would let us do things like our output message box but would probably be a lot more well-behaved and extensible. Here is a brief writeup. It also seems to be pretty lightweight.

A few potential benefits:

Error messages

An example could be in our error messages. Right now we're hand-coding some red ansii and generating a little box like this:

With rich we coulda accomplish something similar with one line:

print(Panel("[white]There was an error in building your book. Look above for the cause.", title="error", style="red",  expand=False, padding=2))

results in

Message boxes

More generally, any time we display message boxes to people we'd have a lot more control over the formatting and style.

Tracebacks

Rich's Tracebacks are generally more nicely-formatted and easy to read.

Rich allows you to suppress traceback levels at the module level, so we could do something like suppress=[click] and then all of the 5-6 click traceback levels would take up much less space.

Rich printing

We could re-use Rich for printing rich text to the console (though we already do this with click.echo so it may not be a huge improvement)

Example closed PR

We had a PR a while back to demonstrate adding Rich to the package, but didn't have time to finish it. It's here in case others want to re-use or pick it up:

• https://github.com/executablebooks/jupyter-book/pull/1665