add github actions

.github/workflows/autotools.yml

@@ -0,0 +1,19 @@
+name: C with autotools
+
+on: [push, pull_request]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v1
+    - name: autogen
+      run: ./autogen.sh
+    - name: configure
+      run: ./configure
+    - name: make
+      run: make
+    - name: make distcheck
+      run: make distcheck