Add polochon download button in the show details

src/public/js/components/shows/details.js

@@ -148,6 +148,7 @@ function Episode(props) {
               />
             )
           })}
+          <DownloadButton data={props.data}/>
         </span>
       </td>
     </tr>
@@ -176,3 +177,17 @@ class Torrent extends React.Component {
     )
   }
 }
+
+function DownloadButton(props) {
+  if (props.data.polochon_url === "") {
+    return null
+  }
+
+  return (
+    <span>
+      <a type="button" className="btn btn-xs btn-warning" href={props.data.polochon_url}>
+          <i className="fa fa-download"></i> Download
+      </a>
+    </span>
+  );
+}