add nrf commandline utility

[AdityaMitra5102]

Add command line utility for nrf

C:\Users\Aditya NK>nitropy-nrf
Usage: nitropy-nrf [OPTIONS] COMMAND [ARGS]...

  Nordic nRF52 DFU/signing utilities.

Options:
  --help  Show this message and exit.

Commands:
  dfu   Perform a DFU transfer.
  keys  Key generation and inspection.
  pkg   Generate DFU packages.

C:\Users\Aditya NK>nitropy-nrf dfu
Usage: nitropy-nrf dfu [OPTIONS] COMMAND [ARGS]...

  Perform a DFU transfer.

Options:
  --help  Show this message and exit.

Commands:
  usb-serial  Send a DFU package over a USB serial port.

C:\Users\Aditya NK>nitropy-nrf keys
Usage: nitropy-nrf keys [OPTIONS] COMMAND [ARGS]...

  Key generation and inspection.

Options:
  --help  Show this message and exit.

Commands:
  display   Display/export the public key derived from KEY_FILE in the...
  generate  Generate a new signing key and write it to KEY_FILE.

C:\Users\Aditya NK>nitropy-nrf pkg
Usage: nitropy-nrf pkg [OPTIONS] COMMAND [ARGS]...

  Generate DFU packages.

Options:
  --help  Show this message and exit.

Commands:
  generate  Generate an application and/or bootloader DFU package.

C:\Users\Aditya NK>

[daringer]

nice, needs Nitrokey/nitrokey-sdk-py#138 merged