Cannot nix-build gradle2nix based on readme

[Profpatsch]

> nix-build -E 'import (fetchTarball "https://github.com/tadfisher/gradle2nix/archive/master.tar.gz")  {}'
error: value is a function while a set was expected

       at /nix/store/fiz86yyci06adkqi9wrasclcvy2amm5x-source/gradle-env.nix:328:5:

          327|   mkGradle = gradleSpec:
          328|     gradleGen.gradleGen {
             |     ^
          329|       inherit (gradleSpec) nativeVersion;
(use '--show-trace' to show detailed location information)

[Profpatsch]

looks like it broke with nixpkgs NixOS/nixpkgs@01f4c7e

[Sintrastes]

@Profpatsch Any workarounds for this?

[chuangzhu]

https://github.com/randomnetcat/gradle2nix works for me

[lorenzleutgeb]

There's a PR ready at #49, and some forks that work.

/cc @tadfisher