Delete media items (#20)

* Added method for deleting media files and their content

* Adds controllers and methods for deleting media and files

* Improved tmpfile setup and teardown for tests

* Actually got tmpfile cleanup running once per suite run

* Finally fixed flash messages

lib/pinchflat/media/media_item.ex

@@ -60,4 +60,9 @@ defmodule Pinchflat.Media.MediaItem do
     |> validate_required(@required_fields)
     |> unique_constraint([:media_id, :source_id])
   end
+
+  @doc false
+  def filepath_attributes do
+    ~w(media_filepath thumbnail_filepath metadata_filepath subtitle_filepaths)a
+  end
 end