message: Prepare the summary partial for page resources
  You can now either set a `featured_image` to use a page resource or
  `featured_image_url` to specify a URL as before.
diff: <article class="list-article">
  + {{ if (or .Params.featured_image .Params.featured_image_url) }}
  + {{ $img_src := "" }}
  {{ if .Params.featured_image }}
  - <div class="col25 article-featured-image"><a href="{{ .Permalink }}"><img class="image"
  - src="{{ .Params.featured_image }}" alt="{{ .Title }}"></a></div>
  + {{ $img_src = (partial "functions/imgURL" (dict "page" .Page "name" (.Params.featured_image) "command" "Resize" "options" "230x")) }}
  + {{ else }}
  + {{ $img_src = .Params.featured_image_url }}
  + {{ end }}
  + <div class="col25 article-featured-image"><a href="{{ .Permalink }}"><img class="image" src="{{ $img_src }}" alt="{{ .Title }}"></a></div>
  {{ end }}
  - <div class="padded {{ if .Params.featured_image }}col75{{end}}">
  + <div class="padded {{ if (or .Params.featured_image .Params.featured_image_url) }}col75{{end}}">
  <a href="{{ .Permalink }}">
  <h1>{{ .Title }}</h1>
  </a>
  