* Skip overwrite voucher file if existing
* changing activation_bytes command behavior
- remove `save` flag
- add `reload` flag
- informational messages are now print to stderr
The command will now save fetched activation bytes to auth file and
will reload it from file. Using `reload` flag will fetch activation
bytes again.
* message handling of download command
Some information messages are now printed out to stderr
* prevent issues when using external login (importing readline module)
* set minimum click version to 7
* bugfixes
# Added
- Set a custom plugin dir via environment variable
- Provide plugin packages where commands can hook in audible command.
# Changed
- Plugin commands are now placed in the command root instead of ``plugin-cmds`` subcommand. So replacing of build-in commands are possible.
# Removed
- The `--config`` option. A custom config dir can now only be set via environment variable.
- The `--plugins`` option. A custom plugin dir can now only be set via environment variable
# Misc
- Some code optimations
