Add github actions workflow file

Author: johejo

.github/workflows/ci.yml

@@ -0,0 +1,23 @@
+name: ci
+on:
+  pull_request:
+    branches:
+      - master
+  push:
+    branches:
+      - master
+jobs:
+  test:
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+        go: ["1.14", "1.15"]
+    runs-on: ${{ matrix.os }}
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-go@v2
+        with:
+          go-version: ${{ matrix.go }}
+      - run: |
+          go test -cover -coverprofile coverage.txt -race -v ./...
+      - uses: codecov/codecov-action@v1

README.md

@@ -3,6 +3,7 @@
 [![codecov](https://codecov.io/gh/mattn/go-shellwords/branch/master/graph/badge.svg)](https://codecov.io/gh/mattn/go-shellwords)
 [![Build Status](https://travis-ci.org/mattn/go-shellwords.svg?branch=master)](https://travis-ci.org/mattn/go-shellwords)
 [![GoDoc](https://godoc.org/github.com/mattn/go-shellwords?status.svg)](http://godoc.org/github.com/mattn/go-shellwords)
+[![ci](https://github.com/mattn/go-shellwords/ci/badge.svg)](https://github.com/mattn/go-shellwords/actions)
 
 Parse line as shell words.