test out github actions

.github/workflows/c.yml

@@ -0,0 +1,18 @@
+name: C CI
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches: 
+      - master
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    
+    steps:
+      - uses: actions/checkout@v1
+      - name: make
+        run: make