Use github actions instead of travis.

Travis seems severely broken for FOSS, so here we go.

Author: black-puppydog

.github/workflows/main.yml

@@ -0,0 +1,39 @@
+name: Node.js CI
+
+on:
+  push:
+    branches: [master]
+  pull_request:
+    branches: [master]
+
+jobs:
+  build:
+    runs-on: ${{ matrix.os }}
+
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [macos-latest, windows-latest, ubuntu-latest]
+        node-version: [10.x, 12.x, 14.x, 15.x]
+
+    steps:
+      - run: git config --global core.autocrlf false
+      - uses: actions/checkout@v2
+      - name: Set up Rust
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+      - name: Use Node.js ${{ matrix.node-version }}
+        uses: actions/setup-node@v1
+        with:
+          node-version: ${{ matrix.node-version }}
+      - run: npm ci
+      # - run: npm test
+      # build (will not publish)
+      - run: npm run build
+        if: github.ref != 'refs/heads/master'
+      # dist (may publish)
+      - run: npm run dist
+        if: github.ref == 'refs/heads/master'
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}