Added GitHub Actions CI

.github/workflows/actions.yml

@@ -0,0 +1,32 @@
+name: Static Site Generator tests
+on:
+  push:
+    branches: [ master ]
+  pull_requests:
+    branches: [ master ]
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        python-version: ["3.6","3.7"]
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v2
+        with:
+          python-version: ${{ matrix.python-version }}
+      - name: Install dependencies
+        run: |
+          python3 -m pip install --upgrade pip
+          python3 -m pip install -r requirements.txt
+          python3 -m pip install -r dev-requirements.txt
+      - name: Format code with black
+        run: |
+          black .
+      - name: Lint with flake8
+        run: |
+          flake8 .
+      - name: Test with pytest
+        run: |
+          pytest tests/