Rename --docs tests file to docs_test.exs

Author: José Valim

…b/elixir/test/elixir/kernel/doc_test.exs …/elixir/test/elixir/kernel/docs_test.exslib/elixir/test/elixir/kernel/doc_test.exs renamed to lib/elixir/test/elixir/kernel/docs_test.exs lib/elixir/test/elixir/kernel/doc_test.exs renamed to lib/elixir/test/elixir/kernel/docs_test.exs

@@ -1,7 +1,7 @@
 Code.require_file "../test_helper.exs", __DIR__
 
-defmodule Kernel.DocTest do
-  use ExUnit.Case
+defmodule Kernel.DocsTest do
+  use ExUnit.Case, async: true
 
   test :compiled_docs do
     path = Path.join(__DIR__, "../fixtures/compiled_with_docs.ex")