Switch to GitHub Actions CI + drop support for old Python/Django

Fixes hzdg#130

.github/workflows/ci.yml

@@ -0,0 +1,30 @@
+name: CI
+on:
+  push:
+    branches:
+      - fork
+      - master
+  pull_request:
+    branches:
+      - fork
+      - master
+jobs:
+  Build:
+    runs-on: ubuntu-20.04
+    strategy:
+      matrix:
+        include:
+          - python-version: '3.8'
+          - python-version: '3.9'
+          - python-version: '3.10'
+          - python-version: '3.11'
+    steps:
+      - uses: actions/checkout@v2
+      - name: 'Set up Python ${{ matrix.python-version }}'
+        uses: actions/setup-python@v4
+        with:
+          python-version: '${{ matrix.python-version }}'
+          cache: pip
+          cache-dependency-path: pyproject.toml
+      - run: pip install -U pip wheel setuptools tox tox-gh
+      - run: tox

pyproject.toml

@@ -17,21 +17,23 @@ maintainers = [
 classifiers = [
     "Environment :: Web Environment",
     "Framework :: Django",
-    "Framework :: Django :: 2.2",
-    "Framework :: Django :: 3.0",
-    "Framework :: Django :: 3.1",
     "Intended Audience :: Developers",
     "License :: OSI Approved :: MIT License",
     "Operating System :: OS Independent",
     "Programming Language :: Python",
     "Programming Language :: Python :: 3",
-    "Programming Language :: Python :: 3.5",
-    "Programming Language :: Python :: 3.6",
     "Programming Language :: Python :: 3.7",
     "Programming Language :: Python :: 3.8",
     "Programming Language :: Python :: 3.9",
+    "Programming Language :: Python :: 3.10",
+    "Programming Language :: Python :: 3.11",
     "Topic :: Internet :: WWW/HTTP",
 ]
+requires-python = ">=3.7"
+
+dependencies = [
+    "django>=3.2",
+]
 
 [project.urls]
 Homepage = "https://github.com/hzdg/django-enumfields"

tox.ini

@@ -1,14 +1,23 @@
 [tox]
 envlist =
-    py{36,37,38,39}-django{22,30,31}
+    py{38,39}-django{32}
+    py{39,310,311}-django{40,41}
 
 [testenv]
 setenv = PYTHONPATH = {toxinidir}
 commands = py.test -s tests --cov=enumfields --cov-report=term-missing
 deps =
     djangorestframework>=3.7
     pytest-django
-    pytest-coverage
-    django22: Django>=2.2,<2.3
-    django30: Django>=3.0,<3.1
-    django31: Django>=3.1,<3.2
+    pytest-cov
+    django32: Django~=3.2.0
+    django40: Django~=4.0.0
+    django41: Django~=4.1.0
+    django42: Django~=4.2.0
+
+[gh]
+python =
+    3.8: py38
+    3.9: py39
+    3.10: py310
+    3.11: py311