Removed Travis automation, added GH Actions build & publish to npm

Author: GreyCat

.github/workflows/build.yml

@@ -0,0 +1,23 @@
+name: npm build
+
+on:
+  push:
+    branches:
+      - master
+  pull_request: {}
+
+jobs:
+  publish-npm:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-node@v1
+        with:
+          node-version: 12
+          registry-url: https://registry.npmjs.org/
+      - run: npm ci
+      - name: Publish to npm
+        run: npm publish --tag next
+        env:
+          NODE_AUTH_TOKEN: ${{secrets.npm_token}}
+        if: github.ref == 'refs/heads/master'

.travis.yml

@@ -1,6 +1,6 @@
 {
   "name": "kaitai-struct",
-  "version": "0.9.0-SNAPSHOT.1",
+  "version": "0.9.0-SNAPSHOT.3",
   "description": "Kaitai Struct: runtime library for Javascript",
   "main": "index.js",
   "repository": {