can't figure out how to add it

[PinkMushroom]

julia --project=. -e 'import Pkg; Pkg.add("https://github.com/kmsquire/ArgParse2.jl")'
ERROR: https://github.com/kmsquire/ArgParse2.jl is not a valid packagename.
The argument appears to be a URL or path, perhaps you meant Pkg.add(PackageSpec(url="...")) or Pkg.add(PackageSpec(path="...")).

I'll forgo the stacktrace unless you need it...