Please use fetchFromGitHub instead of fetchurl when fetching from GH.

@peterhoeg, I would normally use fetchFromGitHub, but this is a special case. The current Nix package doesn't compile from source. Rather, it just downloads a gzipped tarball from this URL:

http://chianti.ucsd.edu/${name}/${name}.tar.gz

That URL works for version 3.6.1, but it doesn't work for version 3.7.1. The equivalent working URL is this:

https://github.com/cytoscape/cytoscape/releases/download/${version}/${name}.tar.gz

My update is very conservative, containing the minimal changes required to bump from 3.6.1 to 3.7.1.

If someone has time, it would definitely be better to get the code like this:

  src = fetchFromGitHub {
    owner = "cytoscape";
    repo = "cytoscape";
    rev = "${version}";
    sha256 = "0jqg3mxvgh9w4h9npbzql78ki03ypa5b3pjgwhivlqwwa60sxnn2";
  };

And then build from source. But I can't guarantee when I'll be able to make that happen, because it'll mean completely rewriting the package.

Makes sense.