More improvements to Kernel typespecs
More improvements to Kernel typespecs

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