Add importing html and save it to Article

Additionally defines a wizard logic which is partially unused yet.

lib/outlook/html_preparations.ex

@@ -11,4 +11,10 @@ defmodule Outlook.HtmlPreparations do
       |> HtmlPreparation.floki_to_internal
       |> HtmlPreparation.set_sibling_with
   end
+
+  def get_tree_items(content_tree) do
+    content_tree
+      |> HtmlPreparation.strip_whitespace_textnodes
+      |> HtmlPreparation.build_indentation_list(0)
+  end
 end