Add a note for binary_part/3 on String.slice/3
Add a note for binary_part/3 on String.slice/3

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