Added meta image link.

Author: evoluteur

index.html

@@ -24,6 +24,10 @@
       name="keywords"
       content="d3, d3.js, dual, range, slider, svg, component, widget"
     />
+    <meta
+      property="og:image"
+      content="https://evoluteur.github.io/d3-dual-range-slider/screenshot.gif"
+    />
     <link rel="icon" type="image/png" href="favicon.png" />
     <meta charset="utf-8" />
     <link rel="stylesheet" type="text/css" href="css/pages.css" />