GitHub Action to run cpplint on all pull requests

.github/workflows/ccpp.yml

+name: cpplint
+on: [push, pull_request]
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v1
+    - uses: actions/setup-python@v1
+    - run: pip install cpplint
+    - run: cpplint --recursive .