Azure IOT Edge V2 on balenaCloud

!!! This is still a Work In Progress !!!

Requirements:

1. Create iot hub on azure portal: https://docs.microsoft.com/en-us/azure/iot-hub/iot-hub-create-through-portal
2. Register a device: https://docs.microsoft.com/en-us/azure/iot-edge/how-to-register-device-portal
3. Copy the primary connection string and add it to Device Environment Variables in your balenaCloud fleet: DEVICE_CONNECTION_STRING.
4. balena push myFleet the this repo to your balenaCloud fleet.

TODO:

• use sed to insert the connection string from an ENV var before the iotedge gets started, so we can have different configuration strings for different devices.
• Improve how waiting for dockerd works.
• Add a Dockerfile.x86 for Intel based machines like Intel NUC or Upboard.