This package is not yet registered on http://pkg.julialang.org/, this is why the following steps are required:
julia
> Pkg.clone("https://github.com/openfisca/OpenFiscaCore.jl")
> Pkg.clone("https://github.com/openfisca/OpenFiscaFrance.jl")
> Pkg.update()
> exit()
julia
> Pkg.test("OpenFiscaCore")
> Pkg.test("OpenFiscaFrance")
> exit()
To download tests from Ludwig, please use the new script in Python repo: download_mes_aides_tests.py (see openfisca/openfisca-france#359)