Create github action script

This adds a new github action script to use GH's native CI, rather than travis-ci.

.github/workflows/ccpp.yml

@@ -0,0 +1,45 @@
+name: FVWM3 CI
+
+on: [ push, pull_request, create ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: install
+      run: |
+        sudo apt install autotools-dev build-essential debhelper dh-autoreconf file fontconfig gettext libfontconfig-dev libfreetype6-dev libfribidi-dev libncurses5-dev libpng-dev libreadline-dev libsm-dev libx11-dev libxcursor-dev libxext-dev libxft-dev libxi-dev libxpm-dev libxrandr-dev libxrender-dev libxt-dev sharutils xsltproc
+        (./autogen.sh && CFLAGS= ./configure)
+        make CFLAGS="-g -O2 -Wall"
+  notification:
+    runs-on: ubuntu-latest
+    name: notifications
+    steps:
+      - name: irc push
+        uses: rectalogic/notify-irc@v1
+        if: github.event_name == 'push'
+        with:
+          channel: "#fvwm"
+          nickname: fvwm3-gh
+          message: |
+            ${{ github.actor }} pushed ${{ github.event.ref }} ${{ github.event.compare }}
+            ${{ join(github.event.commits.*.message) }}
+      - name: irc pull request
+        uses: rectalogic/notify-irc@v1
+        if: github.event_name == 'pull_request'
+        with:
+          channel: "#fvwm"
+          nickname: fvwm3-gh
+          message: |
+            ${{ github.actor }} opened PR ${{ github.event.html_url }}
+      - name: irc tag created
+        uses: rectalogic/notify-irc@v1
+        if: github.event_name == 'create' && github.event.ref_type == 'tag'
+        with:
+          channel: "#fvwm"
+          nickname: fvwm-gh
+          message: |
+            ${{ github.actor }} tagged ${{ github.repository }} ${{ github.event.ref }}