Update contribution guidelines (#2384)
Update contribution guidelines (#2384)

Remove instructions to create an issue for translation, adds link to generated translation report.
nscyclone/elixir-school,doomspork/elixir-school,nscyclone/elixir-school,nscyclone/elixir-school,doomspork/elixir_school,doomspork/elixir_school,doomspork/elixir-school,doomspork/elixir-school,nscyclone/elixir-school,doomspork/elixir_school