[tlbuild] hintview source

[Karl Berry]

Martin has also committed sources for a Unix hint viewer:
web2c/hitexdir/hintview.

It requires a number of libraries: libdl, libglew, libglfw3,
libfreetype, libX11, libXrandr, libXinerama.

It's not part of the build, and there isn't even a configure script. The
idea was just to run make, if you have the libraries, and don't worry
about it, if you don't. Any binaries we distributed for it will be rather
a bonus.

On his web page, Martin provides precompiled Windows and GNU/Linux
executables, as well as an Android executable distributed through the
Play store: http://hint.userweb.mwn.de/hint/hintview.html

That's where we are for now. --thanks, karl.