Instead of all commands (like `load-device`, `change-pin`,
`tezos-sign-tx`, `ethereum-verify-message`...) living in trezorctl.py,
each functional group is now defined in a separate file.
With that, better structuring of the trezorctl command becomes
available:
- instead of `trezorctl set-label`, use `trezorctl set label`
- instead of `trezorctl change-pin`, use `trezorctl set pin`
- instead of `trezorctl enable-passphrase`, use `trezorctl set
passphrase enabled`
For common commands, such as `sign-tx`, it is possible to use the
currency name or shortcut:
- `trezorctl btc sign-tx`
- `trezorctl ethereum sign-tx`
- `trezorctl xtz sign-tx`
- `trezorctl doge sign-tx`
etc.
Some aliases have been retained for better compatibility. For others,
refer to `trezorctl --help` and `trezorctl <command> --help`.
