ci:use github actions to publish to pypi

This closes #94.

.github/workflows/pypi-publish.yml

@@ -0,0 +1,26 @@
+on:
+  push:
+    tags:
+      - v*
+
+jobs:
+  build-n-publish:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Set up Python 3.7
+        uses: actions/setup-python@v2
+        with:
+          python-version: 3.7
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install setuptools wheel
+      - name: Build package
+        run: |
+          python setup.py compile_catalog sdist bdist_wheel
+      - name: pypi-publish
+        uses: pypa/gh-action-pypi-publish@v1.3.1
+        with:
+          user: __token__
+          password: ${{ secrets.pypi_password }}