Start testing with Django 2.2 by default

.travis.yml

@@ -7,7 +7,7 @@ python:
 env:
   # note: latest versions first b/c the top-most is included in new
   # build stages if not specified
-  - DJANGO=2.1
+  - DJANGO=2.2
 stages:
   - django_not_installed
   - django_is_installed

tox.ini

@@ -19,7 +19,7 @@ commands =
     pylint: pylint --rcfile=tox.ini -d missing-docstring,too-many-branches,too-many-return-statements,too-many-ancestors,fixme --ignore=tests pylint_django setup
     readme: bash -c \'python setup.py -q sdist && twine check dist/*\'
     py{36}-django{111,20,-master}: coverage run pylint_django/tests/test_func.py -v
-    py{35,36,37}-django21: coverage run pylint_django/tests/test_func.py -v
+    py{35,36,37}-django22: coverage run pylint_django/tests/test_func.py -v
     clean: find . -type f -name '*.pyc' -delete
     clean: find . -type d -name __pycache__ -delete
     clean: rm -rf build/ .cache/ dist/ .eggs/ pylint_django.egg-info/ .tox/
@@ -32,6 +32,7 @@ deps =
     django111: Django>=1.11,<2.0
     django20: Django>=2.0,<2.1
     django21: Django>=2.1,<2.2
+    django22: Django>=2.2,<3.0
     django-master: Django
     django-master: git+https://github.com/pycqa/astroid@master
     django-master: git+https://github.com/pycqa/pylint@master
@@ -51,6 +52,7 @@ DJANGO =
     1.11: django111
     2.0: django20
     2.1: django21
+    2.2: django22
     master: django-master
 
 [flake8]