tools (common/data_objects): handle messages without body

libervia/backend/tools/common/data_objects.py

@@ -62,7 +62,7 @@ class Message(object):
         try:
             return self._message_data[""]
         except KeyError:
-            return next(iter(self._message_data.values()))
+            return next(iter(self._message_data.values()), "")
 
     @property
     def subject(self):

libervia/backend/tools/xml_tools.py

@@ -1709,7 +1709,7 @@ def quick_note(host, client, message, title="", level=C.XMLUI_DATA_LVL_INFO):
 
 
 def deferred_ui(host, xmlui, chained=False):
-    """create a deferred linked to XMLUI
+    """Create a deferred linked to XMLUI
 
     @param xmlui(XMLUI): instance of the XMLUI
         Must be an XMLUI that you can submit, with submit_id set to ''