punchcard: shift midnight alignment

eodb/events/management/commands/punchcard.py

@@ -16,11 +16,18 @@ class Command(GraphCommand):
         if options.get('committime'):
             datetime_var = 'commit_datetime'
 
+        def hour_shift(x):
+            x = x - 4
+            if x < 0:
+                x += 24
+            return x
+
         for commit in self.get_events(options):
-            coords = (getattr(commit, datetime_var).weekday(), getattr(commit, datetime_var).hour)
+            coords = (getattr(commit, datetime_var).weekday(), hour_shift(getattr(commit, datetime_var).hour))
             infos[coords] = infos[coords] + 1
 
-        draw_punchcard(infos)
+        draw_punchcard(infos,
+                ax2_ticks=list(range(4, 24)) + list(range(4)))
         self.plot(options)
 
 # https://stackoverflow.com/a/14850998