Added github action test workflow.

Removed travis config.
Updated README badge.

.github/workflows/test.workflow.yml

@@ -0,0 +1,43 @@
+name: Tests
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    types: [opened, synchronize, reopened, ready_for_review]
+    branches:
+      - master
+
+jobs:
+  tests:
+    runs-on: ${{ matrix.os }}
+    if: github.event.pull_request.draft == false
+
+    strategy:
+      matrix:
+        os: [ubuntu-latest]
+        node: [8, 10, 12]
+
+    steps:
+      - name: Check out repository
+        uses: actions/checkout@v3
+
+      - uses: actions/setup-node@v3
+        with:
+          node-version: ${{ matrix.node }}
+
+      - name: Update NPM to latest
+        run: npm install npm@latest -g
+
+      - name: Print Node.js and NPM version
+        run: |
+          node -v
+          npm -v
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Run tests
+        timeout-minutes: 5
+        run: npm test

Readme.md

@@ -1,5 +1,5 @@
 # Dox
-[![Build Status](https://travis-ci.org/tj/dox.svg?branch=master)](https://travis-ci.org/tj/dox)
+[![Tests](https://github.com/tj/dox/actions/workflows/test.workflow.yml/badge.svg)](https://github.com/tj/dox/actions/workflows/test.workflow.yml)
 
  Dox is a JavaScript documentation generator written with [node](http://nodejs.org). Dox no longer generates an opinionated structure or style for your docs, it simply gives you a JSON representation, allowing you to use _markdown_ and _JSDoc_-style tags.