Add release workflow

.github/workflows/python-release.yml

@@ -0,0 +1,24 @@
+name: Release to PyPi
+
+on:
+  release:
+    types: [created]
+
+jobs:
+  release:
+    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: Install build requirements
+      run: python -m pip install wheel
+    - name: Build package
+      run: python setup.py sdist bdist_wheel
+    - name: Publish package
+      uses: pypa/gh-action-pypi-publish@master
+      with:
+        user: __token__
+        password: ${{ secrets.pypi_password }}