Feature Request: numfmt input type defaults to 'auto' instead of 'none'

[Oliver Webb]

Hello, first I'd like to say thanks for the GNU coreutils.

When trying to parse numbers with `numfmt`, I noticed
that the input type was 'none' by default. This makes
converting to other formats harder since you have to
specify `--from`. Changing it's default input type to
`auto` wouldn't break compatibility and would allow quick
conversion from SI/IEC-I formats to other ones.

Best Regards,

-   Oliver Webb <aquahobbyist@proton.me>