[KO] Translation of Custom Mix Tasks Lesson (#408)
[KO] Translation of Custom Mix Tasks Lesson (#408)

* copy original file to start translation

* save intermediate work

* [KO] Translation of Custom Mix Tasks Lesson

* accept @riseshia's suggestions

* accept @devleoper's suggestion

nscyclone/elixir-school,ElixirVietnam/elixir-school,doomspork/elixir-school,holsky/elixir-school,doomspork/elixir_school,psantos10/elixir-school,yuriibodarev/elixir-school,holsky/elixir-school,ElixirVietnam/elixir-school,psantos10/elixir-school,holsky/elixir-school,nscyclone/elixir-school,doomspork/elixir_school,huydx/elixir-school,erickgnavar/elixir-school,huydx/elixir-school,doomspork/elixir-school,yuriibodarev/elixir-school,nscyclone/elixir-school,doomspork/elixir_school,huydx/elixir-school,erickgnavar/elixir-school,psantos10/elixir-school,doomspork/elixir-school,ElixirVietnam/elixir-school,erickgnavar/elixir-school,nscyclone/elixir-school,yuriibodarev/elixir-school