[tex-eplain] Treat \refn as a number?

[Karl Berry]

    In older issue of The UK TeX FAQ http://www.tex.ac.uk/faq (at least
    in the one dated 2003-02-06) this issue was `solved' by the
    following definitions:

FWIW, the current http://www.tex.ac.uk/cgi-bin/texfaq2html?label=isitanum 
does not have \futurelet.