Fixs annulations

- Fix oublie de @staticmethod pour Settings.CANCEl_DURATION()
- Mise en cache de Settings.CANCEL_DURATION
- Fix sur cancel_operations : mauvais modèles et at

kfet/models.py

@@ -633,11 +633,17 @@ class Settings(models.Model):
         cache.set('OVERDRAFT_AMOUNT', overdraft_amount)
         return  overdraft_amount
 
+    @staticmethod
     def CANCEL_DURATION():
+        cancel_duration = cache.get('CANCEL_DURATION')
+        if cancel_duration:
+            return cancel_duration
         try:
-            return Settings.setting_inst("CANCEL_DURATION").value_duration
+            cancel_duration = Settings.setting_inst("CANCEL_DURATION").value_duration
         except Settings.DoesNotExist:
-            return timedelta()
+            cancel_duration = timedelta()
+        cache.set('CANCEL_DURATION', cancel_duration)
+        return cancel_duration
 
     @staticmethod
     def create_missing():
@@ -667,6 +673,7 @@ class Settings(models.Model):
     def empty_cache():
         cache.delete_many([
             'SUBVENTION_COF','OVERDRAFT_DURATION', 'OVERDRAFT_AMOUNT',
+            'CANCEL_DURATION',
         ])
 
 class GenericTeamToken(models.Model):