setup pio build workflow for WatsonIOT

.github/workflows/build-fw.yml

@@ -0,0 +1,44 @@
+name: PlatformIO CI
+
+on: [push]
+
+jobs:
+  build:
+
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+        firmwares: [WatsonIoT]  # Add comma seperated path/to/fw folders
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Cache pip
+      uses: actions/cache@v2
+      with:
+        path: ~/.cache/pip
+        key: ${{ runner.os }}-pip-${{ hashFiles('**/requirements.txt') }}
+        restore-keys: |
+          ${{ runner.os }}-pip-
+    - name: Cache PlatformIO
+      uses: actions/cache@v2
+      with:
+        path: ~/.platformio
+        key: ${{ runner.os }}-${{ hashFiles('**/lockfiles') }}
+
+    - name: Set up Python
+      uses: actions/setup-python@v2
+
+    - name: Install PlatformIO
+      run: |
+        python -m pip install --upgrade pip
+        pip install --upgrade platformio
+
+    - name: Install library dependencies
+      run: pio lib -g install knolleary/PubSubClient@^2.8 bblanchon/ArduinoJson@^6.16.1 "adafruit/Adafruit NeoPixel@^1.7.0" smfsw/Queue@^1.9 gmag11/ESPNtpClient@^0.2.5
+
+    - name: Run PlatformIO
+      run: pio ci --lib="." --lib="WatsonIoT/lib/Adxl355" --board=esp32dev -v
+      env:
+        PLATFORMIO_CI_SRC: ${{ matrix.firmwares }}
+        PLATFORMIO_BUILD_UNFLAGS: -Werror=reorder