Verify changes with GitHub Actions

The build on Travis CI fails. I think it is easier to enable GitHub
Actions than to fix the Travis CI build. Also Travis was sold and I'm
not sure about the future of Travis CI.

Author: stefanbirkner

.github/workflows/ci.yml

@@ -0,0 +1,21 @@
+# This workflow will build a Java project with Maven
+# For more information see: https://help.github.com/actions/language-and-framework-guides/building-and-testing-java-with-maven
+
+name: Java CI with Maven
+
+on: [push, pull_request]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-18.04
+
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v2
+    - name: Set up JDK 1.8
+      uses: actions/setup-java@v1
+      with:
+        java-version: 1.8
+    - name: Build with Maven
+      run: mvn -B -Dgpg.skip verify

.travis.yml

@@ -1,6 +1,6 @@
 # Fake SFTP Server Rule
 
-[![Build Status](https://travis-ci.org/stefanbirkner/fake-sftp-server-rule.svg?branch=master)](https://travis-ci.org/stefanbirkner/fake-sftp-server-rule)
+![Build Status Linux](https://github.com/stefanbirkner/fake-sftp-server-rule/workflows/Java%20CI%20with%20Maven/badge.svg?branch=master)
 
 Fake SFTP Server Rule is a JUnit rule that runs an in-memory SFTP server while
 your tests are running. It uses the SFTP server of the
@@ -190,9 +190,10 @@ want to contribute code then
 The basic coding style is described in the
 [EditorConfig](http://editorconfig.org/) file `.editorconfig`.
 
-Fake SFTP Server Rule supports [Travis CI](https://travis-ci.org/) for
-continuous integration. Your pull request will be automatically build by Travis
-CI.
+Fake SFTP Server Rule supports
+[GitHub Actions](https://help.github.com/en/actions) for
+continuous integration. Your pull request will be automatically build by GitHub
+Actions.
 
 
 ## Release Guide