Add Github Actions

.github/workflows/main.yml

@@ -0,0 +1,35 @@
+name: "Main"
+
+on: [push, pull_request]
+
+jobs:
+  lint:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [windows-latest, ubuntu-latest, macos-latest]
+    name: Test on ${{ matrix.os }}
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
+        with:
+          node-version: "14"
+      - run: /usr/bin/Xvfb :99 -screen 0 1024x768x24 > /dev/null 2>&1 & echo "Started xvfb"
+        shell: bash
+        if: ${{ success() && matrix.os == 'ubuntu-latest' }}
+      - run: npm install
+      - name: Cache node modules
+        uses: actions/cache@v2
+        env:
+          cache-name: cache-node-modules
+        with:
+          # npm cache files are stored in `~/.npm` on Linux/macOS
+          path: ~/.npm
+          key: ${{ runner.os }}-build-${{ env.cache-name }}-${{ hashFiles('**/package-lock.json') }}
+          restore-keys: |
+            ${{ runner.os }}-build-${{ env.cache-name }}-
+            ${{ runner.os }}-build-
+            ${{ runner.os }}-
+      - run: npm run lint
+        env:
+          DISPLAY: ":99.0"