Optimize performance of compact records

* Make compact records pure namedtuples (remove all dict behaviour)
* Add profiler decorator for dashboard requests performance analysis
* Introduced new parameter 'collect_profiler_stats' for file name
  where profile stats could be stored
* Fix py33 test failures

Change-Id: Ic5c900047a493541510974e9bc9c161f5606739e

stackalytics/dashboard/helpers.py

@@ -113,12 +113,16 @@ def extend_user(user):
 
 def get_activity(records, start_record, page_size, query_message=None):
     if query_message:
+        # note that all records are now dicts!
+        key_func = operator.itemgetter('date')
         records = [vault.extend_record(r) for r in records]
         records = [r for r in records
                    if (r.get('message') and
                        r.get('message').find(query_message) > 0)]
-    records_sorted = sorted(records, key=operator.itemgetter('date'),
-                            reverse=True)
+    else:
+        key_func = operator.attrgetter('date')
+
+    records_sorted = sorted(records, key=key_func, reverse=True)
 
     result = []
     for record in records_sorted[start_record:]: