CI: automatically update jsapi docs

Use a GitHub Action to keep the docs updated, the current onces are 14
month old and outdated.

Use latest jsdoc package

Add full URL to LuCI.html file in README.md

Ignore generated HTML files via .gitignore

Signed-off-by: Paul Spooren <mail@aparcar.org>

.github/workflows/jsdoc.yml

@@ -0,0 +1,31 @@
+name: GitHub pages
+
+on:
+  push:
+    branches:
+      - master
+
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Install
+        run: npm install
+
+      - name: Build
+        run: npm run doc
+
+      - name: Archive docs as artifact
+        uses: actions/upload-artifact@v2
+        with:
+          name: docs
+          path: ./docs/
+
+      - name: Deploy
+        uses: peaceiris/actions-gh-pages@v3
+        with:
+          deploy_key: ${{ secrets.ACTIONS_DEPLOY_KEY }}
+          publish_dir: ./docs/