Add CI build using GitHub Actions.

.github/workflows/build.yml

@@ -0,0 +1,31 @@
+name: Build
+
+on: [push, pull_request]
+
+defaults:
+  run:
+    shell: bash
+
+jobs:
+  build:
+    runs-on: ${{matrix.os}}
+    strategy:
+      matrix:
+        os: [ ubuntu-18.04, ubuntu-20.04 ]
+    steps:
+      - uses: actions/checkout@v2
+      - name: Install dependencies
+        if: ${{runner.os == 'Linux'}}
+        run:
+          sudo apt-get install libusb-1.0-0-dev pkg-config
+      - name: Build
+        run: |
+          ./autogen.sh
+          mkdir tmp
+          cd tmp
+          ../configure --enable-lights
+          make base-kl
+      - name: Test
+        run: |
+          cd run/dfkfb
+           ../../tmp/bld-kl/kn10-kl dfkfb.ini