Added a setting where the exported excel files should be stored.

Added a option to send the exported excel as mail attachment.

src/membership/models.py

@@ -7,7 +7,7 @@ from os import path
 
 from django.conf import settings
 from django.contrib.auth.models import AbstractUser
-from django.core.urlresolvers import reverse
+from django.urls import reverse
 from django.db import models
 from django.utils import timezone
 from django.utils.translation import ugettext as _
@@ -226,8 +226,8 @@ class Membership(AbstractUser):
         """Save the Useraccount, and add him tho the "Paid Membership" group
         if he activated the "membership" checkbox and has been validated.
 
-        :param args: passed through the save() method from django  
-        :param kwargs: passed through the save() method from django 
+        :param args: passed through the save() method from django
+        :param kwargs: passed through the save() method from django
         """
         super(Membership, self).save(*args, **kwargs)
         if self.confirmed: