This is based on pi4j 2.0 which is in a beta status. I have fixed a few bugs in a local version of pi4j 2.0 to get it to work but I haven't submitted those changes to pi4j yet.
This change requires a migration to Java 11 and will *NOT* be backwards compatible. Upgrading to this hub software will require that java 11 and pigpio be installed on the hub. This can be done from an ssh session with the following commands:
apt-get update
apt-get install openjdk-11-jre-headless
apt-get install pigpio
Alternatively, you can download a new sd image, reflash your sd card, and re-adopt your hub.
Make it possible for a hub to reload a config automatically when it changes without being restarted.
Prevent the auto-calibration on first install from being stomped by the app.
Allow updating the hub software via the app.