v0.12.0

Breaking Changes:

• Previously, it was possible to implicitly include default Kconfig
  settings from the Zephyr examples into client applications. This was
  unintentional and has been fixed. As a result, if your application was
  relying on those defaults, you'll now need to set those Kconfig values
  explicitly in your application.

Added:

• Add socket hello_nrf91_offload Zephyr example to demonstrate DTLS
  sockets offload.
• Zephyr: add rak5010_nrf52840 support to all examples
• ESP-IDF: add fw_update example to demonstrate OTA firmware update
• ESP-IDF: add settings example to demonstrate device settings service

Changed:

• Zephyr: example code now explicitly sources Kconfig.defconfig file to
  select necessary Kconfig symbols from the example common files.
• Zephyr: update runtime settings in examples to take effect without
  needing a reboot
• Update libcoap version to v4.3.4a

Fixed:

• Documentation updates
• Certificate Provisioning: Increase nRF52840 network buffers to avoid
  failing handshakes