initial github actions config. runs basic build under ubuntu

.github/workflows/ccpp.yml

@@ -0,0 +1,22 @@
+name: C/C++ CI
+
+on: [push]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v1
+      with:
+        submodules: true
+    - name: configure
+      run: |
+        sudo apt-get update
+        sudo apt-get install libsdl2-dev libfreeimage-dev libfreetype6-dev libcurl4-openssl-dev rapidjson-dev libasound2-dev libgl1-mesa-dev build-essential cmake fonts-droid-fallback libvlc-dev libvlccore-dev vlc-bin
+      shell: bash
+    - name: make
+      run: |
+        cmake .
+        make
+      shell: bash