Admin mark_safe issue. Fxes #46

Changed to `mark_safe` because `allow_tags` is deprecated in Django 2+.

iprestrict/models.py

@@ -5,6 +5,7 @@
 
 from django.db import models
 from django.utils import timezone
+from django.utils.safestring import mark_safe
 
 try:
     from django.urls import reverse
@@ -253,14 +254,12 @@ def move_up(self):
 
     def move_up_url(self):
         url = reverse('iprestrict:move_rule_up', args=[self.pk])
-        return '<a href="%s">Move Up</a>' % url
-    move_up_url.allow_tags = True
+        return mark_safe('<a href="%s">Move Up</a>' % url)
     move_up_url.short_description = 'Move Up'
 
     def move_down_url(self):
         url = reverse('iprestrict:move_rule_down', args=[self.pk])
-        return '<a href="%s">Move Down</a>' % url
-    move_down_url.allow_tags = True
+        return mark_safe('<a href="%s">Move Down</a>' % url)
     move_down_url.short_description = 'Move Down'
 
     def move_down(self):

requirements-1_11.txt

@@ -0,0 +1,2 @@
+-r common-requirements.txt
+Django>=1.11,<1.12

requirements.txt

@@ -1 +1 @@
-requirements-1_8.txt
+requirements-2_0.txt

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 envlist =
-    {py27,py34,py35,py36}-django-{18,19,110}
+    {py27,py34,py35,py36}-django-{18,19,110,111}
     {py34,py35,py36}-django-{20}
     flake8
 skip_missing_interpreters = True