Add products on billings

apps/treasury/admin.py

@@ -0,0 +1,16 @@
+# Copyright (C) 2018-2020 by BDE ENS Paris-Saclay
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+from django.contrib import admin
+
+from treasury.models import Billing, Product
+
+
+@admin.register(Billing)
+class BillingAdmin(admin.ModelAdmin):
+    list_display = ('id', 'name', 'subject', 'acquitted', )
+
+
+@admin.register(Product)
+class ProductAdmin(admin.ModelAdmin):
+    list_display = ('designation', 'quantity', 'amount', )