Add github CI

Author: mlschroe

.github/workflows/ci.yml

@@ -0,0 +1,29 @@
+---
+name: CI
+
+on:
+  push:
+    branches:
+      - master
+      - 0.6.x
+  pull_request:
+    branches:
+      - master
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Setup
+        run:  |
+          sudo apt-get install cmake
+      - name: Build
+        run:  |
+          mkdir build
+          cd build
+          cmake -DDEBIAN=1 -DMULTI_SEMANTICS=1 ..
+          make
+      - name: Test
+        run:  |
+          make test