package/python-django: security bump to version 1.11.18

Fixes CVE-2019-3498: Content spoofing possibility in the default 404 page

For more details, see the announcement:
https://www.djangoproject.com/weblog/2019/jan/04/security-releases/

Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/python-django/python-django.hash

@@ -1,3 +1,3 @@
-# From https://www.djangoproject.com/m/pgp/Django-1.11.16.checksum.txt
-sha256	29268cc47816a44f27308e60f71da635f549c47d8a1d003b28de55141df75791  Django-1.11.16.tar.gz
+# From https://www.djangoproject.com/m/pgp/Django-1.11.18.checksum.txt
+sha256  73cca1dac154e749b39cc91a54dc876109eb0512a5c6804986495305047066a5  Django-1.11.18.tar.gz
 sha256	b846415d1b514e9c1dff14a22deb906d794bc546ca6129f950a18cd091e2a669  LICENSE

package/python-django/python-django.mk

@@ -4,10 +4,10 @@
 #
 ################################################################################
 
-PYTHON_DJANGO_VERSION = 1.11.16
+PYTHON_DJANGO_VERSION = 1.11.18
 PYTHON_DJANGO_SOURCE = Django-$(PYTHON_DJANGO_VERSION).tar.gz
 # The official Django site has an unpractical URL
-PYTHON_DJANGO_SITE = https://files.pythonhosted.org/packages/35/1d/59836bce4c9cfded261e21c0abd6a4629de6d289522d0fd928117d8eb985
+PYTHON_DJANGO_SITE = https://files.pythonhosted.org/packages/90/84/7981bdfcfa80fe81df5325899f9fc1cbebce1fbe4fac092a32dca00d0ab2
 PYTHON_DJANGO_LICENSE = BSD-3-Clause
 PYTHON_DJANGO_LICENSE_FILES = LICENSE
 PYTHON_DJANGO_SETUP_TYPE = setuptools