Wrapper allowing to install/use StarkWare cairo-lang with nix.

Given that you have nix installed, you can enter an ad-hoc environment with all cairo-* executable available on PATH by running:

nix-shell -E 'import "${(builtins.fetchTarball https://github.com/adrian-gierakowski/cairo-lang-nix/archive/master.tar.gz)}/shell.nix"'

or

nix run -f https://github.com/adrian-gierakowski/cairo-lang-nix/archive/master.tar.gz