Add --color option description to mix moduledoc.
Add --color option description to mix moduledoc.

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