So eh, why are you using GitHub for this? As per GitHub itself: "GitHub is a code hosting platform for version control and collaboration. It lets you and others work together on projects from anywhere."
You're not using it for any of the features, code hosting, collaboration or other, but just as a binary distribution platform. That's what things like Bintray are for, for example. What you're doing kinda goes against the FOSS principles GitHub was built up around and supports.