Run tests in GitHub Actions instead of Travis CI

Replace Travis CI configuration and run trigger file with an equivalent
GitHub Actions workflow to run bats-core units tests on pushes to pull
requests targeting master, or pushes to master itself.

Currently limited to running on Ubuntu 16.04 to avoid OpenSSL warning
mesages from later versions (see #55) from breaking the
(too fragile) tests.

.github/workflows/run-bats-core-tests.yml

@@ -0,0 +1,35 @@
+name: Tests
+
+on:
+  # Only run tests on push to master branch
+  push:
+    branches: [master]
+  # Run tests for all pull request changes targeting master
+  pull_request:
+    branches: [master]
+
+jobs:
+  test:
+    # We use older Ubuntu for now to avoid warning from newer OpenSSL (#55)
+    # which break output expectations in some (fragile) tests
+    runs-on: ubuntu-16.04
+
+    steps:
+    # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
+    - uses: actions/checkout@v2
+
+    - name: Install and set up bats-core
+      run: |
+        git clone https://github.com/bats-core/bats-core.git /tmp/bats-core-repo
+        mkdir -p /tmp/bats-core
+        bash /tmp/bats-core-repo/install.sh /tmp/bats-core
+
+    # Need to configure git globally to avoid errors when we create and use
+    # temporary test-specific Git repos fatal: `empty ident name`
+    - name: Configure dummy Git user.[name,email] values
+      run: |
+        git config --global user.name github-actions-user
+        git config --global user.email [email protected]
+
+    - name: Run tests
+      run: /tmp/bats-core/bin/bats tests/

README.md

@@ -12,6 +12,8 @@ to work normally on your local working copy. You can conveniently store things
 like passwords and private keys within your repository and not have to share
 them with your entire team or complicate your workflow.
 
+![Tests](https://github.com/elasticdog/transcrypt/workflows/Tests/badge.svg)
+
 ## Overview
 
 transcrypt is in the same vein as existing projects like