erp5_core: define what activity_watcher gadget should do when things are not working

If for some reasons, this gadget does not get results (usually due to network failures or
service unavailable for other reasons), do not fail and retry until it works again

product/ERP5/bootstrap/erp5_core/SkinTemplateItem/portal_skins/erp5_core/gadget_activity_watcher.js.js

-/*global window, rJS, RSVP, Handlebars, jIO, location */
+/*global window, rJS, RSVP, Handlebars, jIO, location, console */
 /*jslint nomen: true, maxlen:80, indent:2*/
 (function (rJS, jIO, Handlebars, RSVP, window) {
   "use strict";
@@ -61,6 +61,17 @@
           })
           .push(function () {
             return getDataExamine();
+          })
+          .push(undefined, function (error) {
+            //Exception is raised if network is lost for some reasons,
+            //in this case, try patiently until network is back.
+            //There is probably more clean ways
+            console.log("error", error);
+            return new RSVP.Queue().push(function () {
+              return RSVP.delay(1000);
+            }).push(function () {
+                return getDataExamine();
+              });
           });
       }
       return queue.push(function () {