[tlbuild] asy2.49,libGLEW hacks

[Mojca Miklavec]

Dear Karl & Norbert,

On Wed, 3 Apr 2019 at 04:46, Norbert Preining <preining at logic.at> wrote:
>
> Hi all
>
> in cooperation with John we finally found a solution:
>
> - grep glew 2.1 source code (or use attached files)
> - copy glew.c to the asymptote/ directory
> - copy eglew.h  glew.h  glxew.h  wglew.h to asymptote/GL
>   directory (need to be created)
> - patch the configure.ac:

Could we apply that patch to TL's copy of asy sources to simplify the
work of others? We also ship gc, libatomic etc., so adding a few extra
files doesn't sound like a big of a deal.

(I didn't yet test those instructions, but I assume they work on mac
and elsewhere as well.)

Mojca