Merge pull request #580 from mozilla/fix_unicode_error_log

Convert debug message into unicode string

alerts/lib/alert_plugin_set.py

@@ -10,7 +10,7 @@ class AlertPluginSet(PluginSet):
 
     def send_message_to_plugin(self, plugin_class, message, metadata=None):
         if 'utctimestamp' in message and 'summary' in message:
-            message_log_str = '{0} received message: ({1}) {2}'.format(plugin_class.__module__, message['utctimestamp'], message['summary'])
+            message_log_str = u'{0} received message: ({1}) {2}'.format(plugin_class.__module__, message['utctimestamp'], message['summary'])
             logger.info(message_log_str)
 
         return plugin_class.onMessage(message), metadata