basic support for media:thumbnail (#12)

manifest.json

@@ -2,7 +2,7 @@
 
   "manifest_version": 2,
   "name": "RSSPreview",
-  "version": "2.4",
+  "version": "2.5",
   "author": "Aurelien David",
   "homepage_url": "https://github.com/aureliendavid/rsspreview",
 

rss.xsl

@@ -4,7 +4,8 @@
     xmlns:atom="http://www.w3.org/2005/Atom"
     xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
     xmlns:rss1="http://purl.org/rss/1.0/"
-    exclude-result-prefixes="atom rdf rss1" >
+    xmlns:media="http://search.yahoo.com/mrss/"
+    exclude-result-prefixes="atom rdf rss1 media" >
 
     <xsl:output method="html" indent="yes" encoding="utf-8" />
 
@@ -54,6 +55,9 @@
                 <div class="lastUpdated"><xsl:value-of select="pubDate | atom:updated | rss1:pubDate" /></div>
             </h3>
 
+            <xsl:if test='.//media:thumbnail/@url'>
+                <img class="mediaThumb" src="{ .//media:thumbnail/@url }" width="{ .//media:thumbnail/@width }" height="{ .//media:thumbnail/@height }" />
+            </xsl:if>
             <xsl:choose>
               <xsl:when test="atom:summary">
                 <div class="feedRawContent" desctype="{atom:summary/@type}">