bug#1476: 23.0.60; spelling of (un)writeable should be (un)writable

[Drew Adams]

> > But Emacs has standardized on American spelling. American 
> > usage generally drops a final "e" when adding suffix "able".
> 
> If that is your argument (and I'm OK with it, BTW), you should have
> said so, and not pass one of the alternatives as less correct, or
> uncommon, or obsolete.

I took it as understood that Emacs uses American spelling (we've been through
that before, right Juanma?). And I never said that "writeable" was obsolete.

"Writeable" is less correct _for Emacs_, because Emacs tries to adopt common
usage and American spelling.

I specifically cited other software bug reports for "writeable" and argued for
consistency on that basis. IOW, it's not just American usage; it is a more
common usage (as you yourself showed using Google), and especially so in
software.

I quoted the `findutils' bug that showed that `ispell' doesn't recognize
"writeable". It is `ispell' that passed "writeable" off as less correct.

Support by software tools is the kind of thing that should be important to us,
not whether OED finds that it's OK to use either spelling. This is not about OED
vs Webster's or the Brits vs the Yanks. It's about helping Emacs users.

My argument from the beginning (see the bug report) was that "writeable" is less
helpful because Emacs users looking for it (e.g. with grep, ispell, Emacs
search) will be less likely to find it.