Add CI action workflow

.github/workflows/ci.yml

@@ -0,0 +1,38 @@
+name: CI
+on: [pull_request]
+jobs:
+  Test:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python:
+          - version: 3.5
+            toxenv: py35
+          - version: 3.6
+            toxenv: py36
+          - version: 3.7
+            toxenv: py37
+          - version: 3.8
+            toxenv: py38
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up Python ${{ matrix.python.version }}
+        uses: actions/setup-python@v1
+        with:
+          python-version: ${{ matrix.python.version }}
+      - name: Run ${{ matrix.python.toxenv }} tests via tox
+        run: |
+          pip install tox==3.14.5
+          tox -e ${{ matrix.python.toxenv }}
+  Check:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up Python 3.7
+        uses: actions/setup-python@v1
+        with:
+          python-version: 3.7
+      - name: Run meta checks via tox
+        run: |
+          pip install tox==3.14.5
+          tox -e format -e static -e docs