package/python-django: security bump to version 1.11.20

Fixes the following security issues:

CVE-2019-6975: Memory exhaustion in django.utils.numberformat.format()

If django.utils.numberformat.format() – used by contrib.admin as well as the
the floatformat, filesizeformat, and intcomma templates filters – received a
Decimal with a large number of digits or a large exponent, it could lead to
significant memory usage due to a call to '{:f}'.format().

To avoid this, decimals with more than 200 digits are now formatted using
scientific notation.

https://docs.djangoproject.com/en/2.1/releases/1.11.19/

1.11.19 contained a packaging error, fixed by 1.11.20:

https://docs.djangoproject.com/en/2.1/releases/1.11.20/

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-1.11.18.checksum.txt
-sha256  73cca1dac154e749b39cc91a54dc876109eb0512a5c6804986495305047066a5  Django-1.11.18.tar.gz
+# From https://www.djangoproject.com/m/pgp/Django-1.11.20.checksum.txt
+sha256  43a99da08fee329480d27860d68279945b7d8bf7b537388ee2c8938c709b2041  Django-1.11.20.tar.gz
 sha256	b846415d1b514e9c1dff14a22deb906d794bc546ca6129f950a18cd091e2a669  LICENSE

package/python-django/python-django.mk

@@ -4,10 +4,11 @@
 #
 ################################################################################
 
-PYTHON_DJANGO_VERSION = 1.11.18
+PYTHON_DJANGO_VERSION = 1.11.20
 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/90/84/7981bdfcfa80fe81df5325899f9fc1cbebce1fbe4fac092a32dca00d0ab2
+PYTHON_DJANGO_SITE = https://files.pythonhosted.org/packages/99/2a/6cb6fdae67a101e19cd02b1af75131eee51b8dcd0cc22c9cfdd2270b5715
+
 PYTHON_DJANGO_LICENSE = BSD-3-Clause
 PYTHON_DJANGO_LICENSE_FILES = LICENSE
 PYTHON_DJANGO_SETUP_TYPE = setuptools