Improvements to the CLI output as well as converging towards
`termion` as a backend.
The crates we were using for prompting and spinners were based on
a terminal backend called `console`, which is not really used
anywhere else. There were also limitations in terms of the output
of these crates.
Therefore, we switched to the `inquire` crate for prompting, using
the `termion` backend, which is very standard.
Additionally, we simplify the terminal output to use symbols:
! for Warning
✓ for Success
✗ for Error
... Instead of a mix of words and symbols.
We also include a modified version of the `yansi` crate which plays
well with our table formatting functions by automatically truncating
and padding output in a unicode-aware way.
0a93fa833e