test: hello github CI, bye travis and appveyor

.github/workflows/ci.yml

@@ -0,0 +1,26 @@
+name: Install and test amunet
+on: [push, pull_request]
+env:
+  CI: true
+
+jobs:
+  build:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        node-version: [10.x, 12.x, 13.x]
+        os: [ubuntu-latest, windows-latest]
+    steps:
+    - uses: actions/checkout@v1
+    - name: Use Node.js ${{ matrix.node-version }}
+      uses: actions/setup-node@v1
+      with:
+        node-version: ${{ matrix.node-version }}
+    - run: npm install
+    - run: npm run build --if-present
+    - run: npm test
+    - name: Coveralls
+      uses: coverallsapp/github-action@master
+      with:
+        github-token: ${{ secrets.GITHUB_TOKEN }}