Migrate from Travis CI to Github Actions

Author: eht16

.github/workflows/tests.yml

@@ -0,0 +1,39 @@
+#
+# This software may be modified and distributed under the terms
+# of the MIT license.  See the LICENSE file for details.
+
+name: CI Tests
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  test:
+    name: Python ${{ matrix.python }}
+    runs-on: ubuntu-20.04
+    strategy:
+      matrix:
+        python: ['3.6', '3.7', '3.8', '3.9']
+      fail-fast: false
+
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Setup Python
+        uses: actions/setup-python@v2
+        with:
+          python-version: ${{ matrix.python }}
+
+      - name: Update Pip
+        run: pip install --upgrade pip setuptools
+
+      - name: Install Tox
+        run: pip install tox
+
+      - name: Run tests
+        run: tox -e py