Maybe because it is not registered. Try `Pkg.clone()`.
On Thursday, March 10, 2016 at 7:22:42 AM UTC+1, Christoph Ortner wrote:
>
>
> Pkg.add("Plots")
>
> seems to be broken?
>
>
> julia> Pkg.add("Plots")
> fatal: Not a git repository (or any of the parent directories): .git
>
