Bug#314934: locale: document options like charmap

[Kurt Roeckx <kurt@roeckx.be>]

I always have to go and search what the option is to show the current
charmap.  It's documented in nl_langinfo(3), but it would be nice that
it was documented in either the locale manpage, or that the locale tool
could show it itself.

By guessing from the same manpage I could atleast find those
additional names that locale supports:
d_fmt, d_t_fmt, t_fmt, t_fmt_ampm.

I'm guessing there are more.  It would be nice if this was better
documented somewhere.


Kurt