[REQUEST] CC253x (CC2530/CC2531) flasher via zigpy-znp CLI tools

[Hedda]

Since already have other flashers could be nice to add a "TubesZB: TI CC253x Flasher Add-on" based on zigpy-znp CLI tools?

FYI, zigpy-znp can be used as stand-alone command line tool to flash Zigbee NCP application firmware CC2530/CC2531 adapters:

• https://github.com/zigpy/zigpy-znp/blob/dev/TOOLS.md
  • https://github.com/zigpy/zigpy-znp/blob/dev/TOOLS.md#cc2531-tools
    • https://github.com/zigpy/zigpy-znp/blob/dev/TOOLS.md#flash-operations
      • https://github.com/zigpy/zigpy-znp/blob/dev/TOOLS.md#flash-read
      • https://github.com/zigpy/zigpy-znp/blob/dev/TOOLS.md#flash-write

It would probably be a good idea to backup old firmware to file by default so there is an option to go back to the old version.

PS: Probably also be a good idea if it was possible to by default do an automation Zigbee network backup before flashing -> #2