Initial Import

git submodule used to bundle libsodium, latest release tag (0.4.5)
also there is a gem dependency specified in gemspec file:

    spec.add_runtime_dependency "rbnacl", "~> 3.0", ">= 3.0.1"

`>= 3.0.1` pointed because `3.0.0` is not compatible with this and will not work, so we need to bump `rbnacl` version.