Add PlatformIO Github Actions workflow (#55)

And add badges for both electronics and pio actions to README

Updates #49

.github/workflows/pio.yml

@@ -0,0 +1,50 @@
+name: PlatformIO CI
+
+on:
+  push:
+  pull_request:
+
+jobs:
+  pio-build:
+    runs-on: ubuntu-20.04
+
+    steps:
+    - name: Checkout code
+      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
+      id: pio_install
+      run: |
+        python -m pip install --upgrade pip
+        pip install --upgrade platformio
+
+    - name: Build Firmware (view)
+      # Run regardless of other build step failures, as long as setup steps completed
+      if: always() && steps.pio_install.outcome == 'success'
+      run: |
+        pio run -d ./firmware \
+          -e view \
+
+    - name: Build Firmware (handheld_tdisplay)
+      # Run regardless of other build step failures, as long as setup steps completed
+      if: always() && steps.pio_install.outcome == 'success'
+      run: |
+        pio run -d ./firmware \
+          -e handheld_tdisplay \

README.md

@@ -3,6 +3,9 @@ SmartKnob is an open-source input device with software-configurable endstops and
 
 A brushless gimbal motor is paired with a magnetic encoder to provide closed-loop torque feedback control, making it possible to dynamically create and adjust the feel of detents and endstops.
 
+[![Build Status](https://github.com/scottbez1/smartknob/actions/workflows/electronics.yml/badge.svg?branch=master)](https://github.com/scottbez1/smartknob/actions/workflows/electronics.yml)
+[![Build Status](https://github.com/scottbez1/smartknob/actions/workflows/pio.yml/badge.svg?branch=master)](https://github.com/scottbez1/smartknob/actions/workflows/pio.yml)
+
 # Designs
 
 ## SmartKnob View