correct the datetimefield on the orders model

In Django it's better to use timezone.now instead of datetime.now()
this is because it has additional settings for timezones which this
way wouldn't get reflected in the attributes and lead to wrong
datetime values.

django/didgeridoo/webshop/models.py

@@ -2,7 +2,7 @@ from decimal import Decimal
 from django.core.validators import MinValueValidator
 from django.db import models
 from django.contrib.auth.models import User
-import datetime
+from django.utils import timezone
 
 
 class Option(models.Model):
@@ -86,7 +86,7 @@ class Order(models.Model):
     user = models.ForeignKey(User, on_delete=models.CASCADE)
     article = models.ManyToManyField(Article, through='OrderPosition')
     status = models.ForeignKey(OrderStatus)
-    date = models.DateTimeField(default=datetime.datetime.now())
+    date = models.DateTimeField(default=timezone.now)
 
 
 class OrderPosition(models.Model):