First try at github actions.

.github/workflows/build.yml

@@ -0,0 +1,20 @@
+name: Build and test (single linux distro)
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v1
+    - name: bootstrap
+      run: ./bootstrap
+    - name: configure
+      run: ./configure
+    - name: make
+      run: make
+    - name: make check
+      run: make check
+    - name: make distcheck
+      run: make distcheck
+