Fixed Bug in stats aggregation

The check for aggregation was too broad and hence was adding together
totals based on template_id and not the unqiue combination of
template id, month and year.

- Added test to test for the failure
- Added check and a test to for template_id, mon and year matches
- Celery process name did not match the task

app/dao/services_dao.py

@@ -571,7 +571,7 @@ def dao_fetch_monthly_historical_usage_by_template_for_service(service_id, year)
         extract('year', year).label('year'),
         func.count().label('count')
     ).join(
-        Template, Notification.template_id == Template.id
+        Template, Notification.template_id == Template.id,
     ).filter(
         Notification.created_at >= start_date
     ).group_by(
@@ -586,7 +586,9 @@ def dao_fetch_monthly_historical_usage_by_template_for_service(service_id, year)
     for today_result in today_results:
         add_to_stats = True
         for stat in stats:
-            if today_result.template_id == stat.template_id:
+            if today_result.template_id == stat.template_id and \
+                            today_result.month == stat.month and \
+                            today_result.year == stat.year:
                 stat.count = stat.count + today_result.count
                 add_to_stats = False