We don't use custom names and the only place where custom method option
is used it provides the default name and can be omitted.
Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>
Add `subnet` command which contains all subnet-related commands. Add
sub-commands:
* `create` for creation;
* `remove` for removal;
* `get` for reading;
* `admin` for admin management;
* `client` for client management.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>