add github actions

Author: feross

.github/dependabot.yml

@@ -0,0 +1,15 @@
+version: 2
+updates:
+  - package-ecosystem: npm
+    directory: /
+    schedule:
+      interval: daily
+    labels:
+      - dependency
+    versioning-strategy: increase-if-necessary
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: daily
+    labels:
+      - dependency

.github/workflows/ci.yml

@@ -0,0 +1,23 @@
+name: ci
+'on':
+  - push
+  - pull_request
+jobs:
+  test:
+    name: Node ${{ matrix.node }} / ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os:
+          - ubuntu-latest
+        node:
+          - '14'
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v2
+        with:
+          node-version: ${{ matrix.node }}
+      - run: npm install
+      - run: npm run build --if-present
+      - run: npm test