Add github workflow for CI

.github/main.yml

@@ -0,0 +1,34 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+
+jobs:
+  tests:
+    runs-on: ubuntu-latest
+    if: github.event_name == 'pull_request'
+
+    steps:
+      - uses: actions/checkout@v1
+
+      - name: Build image
+        run: ./build.sh
+
+      - name: Run tests
+        run: ./tests/test.sh
+
+  deploy:
+    runs-on: ubuntu-latest
+    if: github.event_name == 'push'
+
+    steps:
+      - uses: actions/checkout@v1
+
+      - name: Log in to dockerhub
+        run: echo "${{ secrets.DOCKERHUB_TOKEN }}" | docker login -u ${{ secrets.DOCKERHUB_USERNAME }} --password-stdin
+
+      - name: Deploy image
+        run: ./build.sh --push --latest