Doxygen: Instruct GitHub Actions to build documentation on push

Signed-off-by: Simon Rozman <simon@rozman.si>

.github/workflows/main.yml

@@ -0,0 +1,39 @@
+# This is a basic workflow to help you get started with Actions
+
+name: Doxygen Action
+
+# Controls when the action will run. Triggers the workflow on push or pull request
+# events but only for the master branch
+on:
+  push:
+    branches: [ master ]
+
+
+  
+# A workflow run is made up of one or more jobs that can run sequentially or in parallel
+jobs:
+  # This workflow contains a single job called "build"
+  build:
+    # The type of runner that the job will run on
+    runs-on: ubuntu-latest
+
+    # Steps represent a sequence of tasks that will be executed as part of the job
+    steps:
+    # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
+    - uses: actions/checkout@v2
+        
+    - name: Doxygen Action
+      uses: mattnotmitt/doxygen-action@v1.1.0
+      with:
+        # Path to Doxyfile
+        doxyfile-path: "./Doxyfile" # default is ./Doxyfile
+        # Working directory
+        working-directory: "." # default is .
+    
+    - name: Deploy
+      uses: peaceiris/actions-gh-pages@v3
+      with:
+        github_token: ${{ secrets.GITHUB_TOKEN }}
+        # Default Doxyfile build documentation to html directory. 
+        # Change the directory if changes in Doxyfile
+        publish_dir: ./doc/html