Fix warnings on IEx
Fix warnings on IEx

joshprice/elixir,ggcampinho/elixir,elixir-lang/elixir,kimshrier/elixir,pedrosnk/elixir,ggcampinho/elixir,michalmuskala/elixir,kelvinst/elixir,kimshrier/elixir,pedrosnk/elixir,kelvinst/elixir