Azure IoT Device SDK / Edge Modules preview

pre-release for the modules-preview branch

• introducing the new ModuleClient
• Modules can:
  • connect to Edge Hub or IoT Hub
  • send telemetry
  • use Azure IoT Edge routing feature with inputs and outputs (only available when connecting to an Edge Hub)
  • use their twin
  • receive method requests
• Known limitations of this preview version:
  • receive C2D messages
  • upload files
  • use X509 authentication