Fix review issues from commit 2a21d75

1. Rename goto_engineering_post_page/2 to visit_engineering_path/2 for
   better accuracy (used for both post pages and tag pages)

2. Simplify Makefile test target by removing explicit ecto.create and
   ecto.migrate commands (mix test handles migrations automatically)

3. Update blog_test.exs header comment to reflect actual changes made

4. Move Sandbox alias to top level in data_case.ex

app/test/support/data_case.ex

@@ -14,10 +14,10 @@ defmodule Firehose.DataCase do
   this option is not recommended for other databases.
   """
 
-  use ExUnit.CaseTemplate
-
   alias Ecto.Adapters.SQL.Sandbox
 
+  use ExUnit.CaseTemplate
+
   using do
     quote do
       alias Firehose.Repo