[dev-context] supp-pdf commented in context.tex

[Duncan Hothersall]

On line 130 in context.tex, \input supp-pdf.tex has been commented out.
I assume this is because its functionality has been superseded by
something else (pdfetex extensions?) In any case, I have no problems
when running pdfetex jobs, but: running jobs with the aleph engine this
ommission causes errors:

! Undefined control sequence.
\dogetfiguresizepdf ...3#4#5#6->\dogetPDFmediabox

when using \externalfigure and suchlike.

Is it safe for me to just uncomment that line in context.tex (which
fixes the problem here) or is that risky for other things?

Thanks,

Duncan