MASTER_SITES=GH? like SF

[Nuno Teixeira]

Hello,

I will use graphics/glfw port as an example:

MASTER_SITES= SF

The project moved to github so I will prefer use GH releases instead of SF:

MASTER_SITES=https://github.com/glfw/glfw/releases/download/${PORTVERSION}/
works ok.

MASTER_SITES= GH:

=> glfw-3.3.2.zip doesn't seem to exist in /work/DISTFILES/.
===> /!\ Error /!\
     The :DEFAULT group used for glfw-3.3.2.zip is missing
     from MASTER_SITES. Check for typos, or errors.
*** Error code 1

Thanks,

Nuno Teixeira