Add cover images to RSS

layouts/_default/rss.xml

@@ -33,6 +33,7 @@
       {{ with .Site.Author.email }}<author>{{.}}{{ with $.Site.Author.name }} ({{.}}){{end}}</author>{{end}}
       <guid>{{ .Permalink }}</guid>
       <description>{{ cond (isset .Params "description") .Params.description (.Summary | html) }}</description>
+      {{ with .Resources.GetMatch "{cover.*,*.jpg,*.png,*.jpeg}" }}<enclosure url="{{ .Permalink }}" type="{{ .MediaType }}" />{{ end }}
     </item>
     {{ end }}
   </channel>