Fixed doc typos in IEx.Helpers
Fixed doc typos in IEx.Helpers

antipax/elixir,kelvinst/elixir,joshprice/elixir,pedrosnk/elixir,ggcampinho/elixir,antipax/elixir,elixir-lang/elixir,lexmag/elixir,michalmuskala/elixir,gfvcastro/elixir,beedub/elixir,kimshrier/elixir,pedrosnk/elixir,kimshrier/elixir,gfvcastro/elixir,ggcampinho/elixir,beedub/elixir,lexmag/elixir,kelvinst/elixir