[add] github actions

.github/workflows/reviewdog.yml

@@ -0,0 +1,22 @@
+name: reviewdog
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  vint:
+    name: runner / vint
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: vint
+        uses: reviewdog/action-vint@v1
+        with:
+          github_token: ${{ secrets.github_token }}
+          level: error
+          reporter: github-pr-check

README.md

@@ -1,4 +1,4 @@
-# vim-airline-themes [![Build Status](https://travis-ci.org/vim-airline/vim-airline-themes.svg?branch=master)](https://travis-ci.org/vim-airline/vim-airline-themes)
+# vim-airline-themes [![Build Status](https://travis-ci.org/vim-airline/vim-airline-themes.svg?branch=master)](https://travis-ci.org/vim-airline/vim-airline-themes) [![reviewdog](https://github.com/vim-airline/vim-airline-themes/workflows/reviewdog/badge.svg?branch=master)](https://github.com/vim-airline/vim-airline-themes/actions?query=workflow%3Areviewdog+event%3Apush+branch%3Amaster)
 
 This is the official theme repository for [vim-airline][11]