Change return format of MachinesStatus

  * More handy to work with defined dict, instead of parsing string

Change-Id: I827dc11ef73e314cd6c7660610f1e2f11ddc7119
diff --git a/_modules/maas.py b/_modules/maas.py
index e545a53..6624f94 100644
--- a/_modules/maas.py
+++ b/_modules/maas.py
@@ -672,9 +672,10 @@
                 continue
             status = status_name_dict[machine['status']]
             summary[status] += 1
-            res.append('hostname:{},system_id:{},status:{}'
-                       .format(machine['hostname'], machine['system_id'],
-                               status))
+            res.append(
+                {'hostname': machine['hostname'],
+                 'system_id': machine['system_id'],
+                 'status': status})
         return {'machines': res, 'summary': summary}