Add GitHub Actions for CI (#26)

.github/workflows/test.yml

@@ -0,0 +1,46 @@
+name: Node CI
+
+on:
+  push:
+    branches:
+    - master
+    tags:
+    - '!*'
+  pull_request:
+
+jobs:
+  build:
+    name: Test Node.js ${{ matrix.node-version }} on ${{ matrix.os }}
+
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest]
+        node-version: [8.x, 10.x, 12.x, 14.x]
+
+    runs-on: ${{ matrix.os }}
+
+    steps:
+    - uses: actions/checkout@v1
+
+    - name: Use Node.js ${{ matrix.node-version }}
+      uses: actions/setup-node@v1
+      with:
+        node-version: ${{ matrix.node-version }}
+
+    - name: Print Node.js Version
+      run: node --version
+
+    - name: Install Dependencies
+      run: npm install
+      env:
+        CI: true
+
+    - name: Run "build" step
+      run: npm run build --if-present
+      env:
+        CI: true
+
+    - name: Run tests
+      run: npm test
+      env:
+        CI: true