Add action to publish cpp api documents (#317)

.github/workflows/publish_cpp_api_docs.yml

@@ -0,0 +1,32 @@
+name: Documentation
+
+# Controls when the action will run. Triggers the workflow on push or pull request
+# events but only for the master branch
+on:
+  push:
+    branches: [ doxygen ]
+
+jobs:
+  build-documentation:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    
+    # Build the HTML documentation
+    - name: Doxygen Action
+      uses: mattnotmitt/doxygen-action@v1.1.0
+      with:
+          doxyfile-path: ./Doxyfile
+          working-directory: .
+    
+    # Deploy the HTML documentation to GitHub Pages
+    - name: GH Pages Deployment
+      uses: peaceiris/actions-gh-pages@v3
+      with:
+        github_token: ${{ secrets.JASON }}
+        publish_dir: ./docs/html/
+        enable_jekyll: false
+        allow_empty_commit: false
+        force_orphan: true
+        publish_branch: gh-pages