[Toybox] help text

[Rob Landley]

I think there's a missing documentation section in www/code.html or design.html
or maybe even the FAQ: some help text rationale and/or consistency guidelines.

I'm looking at readelf.c cleanup (no promises) and the -W option says "default
in toybox". I always just say default, the in toybox part is implicit, but the
bigger issue is I generally don't put flags that do literally nothing (and are
merely ignored for compatibility) in the help text, on the theory the help text
tells somebody who doesn't know how to use the command how to use the command.
If you literally never need to set this flag, and our support is entirely
ignoring it when it's supplied to avoid breaking scripts and such, telling
people they _can_ say it without breaking stuff it seems more confusing than
helpful? (It doesn't _do_ anything...)

I thought I'd write a mailing list message about it (and let people disagree if
they're going to), but mailing list messages get buried over time and... this is
coding style, maybe? (There's a bit on toys/help.h the file, help text is
mentioned in the creating-a-command checklist...)

Hmmm...

Rob