Improve html tree component

lib/outlook_web/view_helpers.ex

@@ -18,4 +18,13 @@ defmodule OutlookWeb.ViewHelpers do
   def strip_links(html) do
     raise "Yet to be implemented!"
   end
+
+  def elipsed_text(text, length) do
+    if String.length(text) < length do
+      text
+    else
+      part_length = (length - 3) / 2  |> trunc()
+      "#{String.slice(text, 0..part_length)} … #{String.slice(text, -part_length..-1)}"
+    end
+  end
 end