Creation of the Stock list, edit, create views and creation StockItem create view

counter/views.py

@@ -443,6 +443,11 @@ class CounterLogout(RedirectView):
 class CounterAdminTabsMixin(TabedViewMixin):
     tabs_title = _("Counter administration")
     list_of_tabs = [
+            {
+                'url': reverse_lazy('stock:list'),
+                'slug': 'stocks',
+                'name': _("Stocks"),
+                },
             {
                 'url': reverse_lazy('counter:admin_list'),
                 'slug': 'counters',