bug#47103: numfmt: invalid suffix 'k'

[Daniel Callejas Sevilla]

Hello,

the SI prefix for 'a thousand' is a lowercase k and not an uppercase K [1].

The default behavior of numfmt with '--from=si' option is therefore
contrary to expectation:

$ numfmt --from=si
 500k    # Should be accepted as valid SI
 numfmt: invalid suffix in input: ‘500k’

$ numfmt --from=si
 500K    # Should result in error, 'K' stands for kelvin unit.
 500000

$ numfmt --version
 numfmt (GNU coreutils) 8.26
 Packaged by Cygwin (8.26-2)
 Copyright (C) 2016 Free Software Foundation, Inc.
 License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.
 This is free software: you are free to change and redistribute it.
 There is NO WARRANTY, to the extent permitted by law.

 Written by Assaf Gordon.


Best regards,
Daniel.

[1] Page 143 of https://www.bipm.org/en/publications/si-brochure/