Batch plugin to be able to work even if there are no operators

dream/plugins/Batches/BatchesOperatorSpreadsheet.py

@@ -18,11 +18,13 @@ class BatchesOperatorSpreadsheet(plugin.OutputPreparationPlugin):
     scheduleSheet.write(rowIndex,3,'End Time',headingStyle)
     rowIndex+=1
     
+    solutionList=None
     # get the result the the router gives
     for element in data['result']['result_list'][-1]['elementList']:
         if element['_class']=='Dream.SkilledRouter':
             solutionList=element['results']['solutionList']
     
+    if solutionList:
         # create a list with all the operator ids that were at least in one allocation
         operatorList=[]
         for record in solutionList: