workflow: add github action to continuous integration

actions:
* install, build and test
* deploy itowns.github.io if merged in master

.github/workflows/integration.yml

@@ -0,0 +1,91 @@
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+name: integration
+env:
+  CI: true
+
+jobs:
+  tests:
+    name: build and test
+    runs-on: ubuntu-latest
+    steps:
+
+    - uses: actions/checkout@v1
+
+    - name: Use Node.js 15.x
+      uses: actions/setup-node@v1
+      with:
+        node-version: 15.x
+    # install package
+    # TODO: add cache npm to speed up installing
+    - name: Install packages
+      run: npm ci
+    # Prepare before build
+    - name: Prepare
+      run: npm run prepare
+    # check linter
+    - name: Linter
+      run: npm run lint -- --max-warnings=0
+    # Build bundle
+    - name: Build bundle
+      if: ${{ success() }}
+      run:  npm run build
+    # run unit tests
+    - name: Unit tests
+      run: npm run test-with-coverage_lcov
+    # run functional tests
+    # TODO functional tests don't stop if one fails
+    - name: Functional tests
+      if: ${{ success() }}
+      run: npm run test-functional
+    # build doc
+    - name: Build docs
+      if: ${{ success() }}
+      run: npm run doc -- -d buildDocs
+    # prepare archive to deploying
+    - name: Archive production artifacts
+      if: ${{ success() && github.ref == 'refs/heads/master' }}
+      uses: actions/upload-artifact@v2
+      with:
+        name: dist-itowns
+        path: |
+          dist/**/*.js
+          examples
+          buildDocs
+
+    - name: Coveralls
+      uses: coverallsapp/github-action@master
+      with:
+        github-token: ${{ secrets.GITHUB_TOKEN }}
+  deploy:
+    needs: tests
+    if: ${{ github.ref == 'refs/heads/master' }}
+    runs-on: ubuntu-latest
+    name: deploy
+    steps:
+    - name: Download bundle
+      uses: actions/download-artifact@v2
+      with:
+        name: dist-itowns
+    - name: build site
+      run: |
+        mkdir -p itowns/dist
+        cp -R dist/*.js itowns/dist/
+        cp -R examples itowns/
+        cp -R buildDocs itowns/docs
+
+    - name: Deploy to github
+      uses: peaceiris/actions-gh-pages@v3
+      with:
+        deploy_key: ${{ secrets.ACTIONS_DEPLOY_KEY }}
+        external_repository: iTowns/itowns.github.io
+        publish_dir: ./itowns
+        destination_dir: ./itowns
+        publish_branch: master
+        enable_jekyll: true