[tlbuild] pretest initial builds please

[Marc Baudoin]

Karl Berry <karl at freefriends.org> écrit :
> As far as I know we are ready to start updating binaries for the TL17
> pretest. Last night's update of tlnet was the last for TL16.

pdfLaTeX crashes on NetBSD/amd64 on even a trivial document:

!pdfTeX error: pdflatex (file /usr/local/texlive/2017/texmf-var/fonts/map/pdftex/updmap/pdftex.map): buffer overflow at file ../../../texk/web2c/pdftexdir/mapfile.c, line 416