DownloadController bugfix

vospace-ui-backend/src/main/java/it/inaf/ia2/vospace/ui/controller/DownloadController.java

@@ -55,6 +55,7 @@ public class DownloadController {
 
         Protocol httpProtocol = new Protocol();
         httpProtocol.setUri("ivo://ivoa.net/vospace/core#httpget");
+        transfer.getProtocols().add(httpProtocol);
 
         Protocol httpsProtocol = new Protocol();
         httpsProtocol.setUri("ivo://ivoa.net/vospace/core#httpsget");