As mentioned in #32, there is a need to remove gogoproto usage from NeoFS API
since this plugin is not cross-language. This commit removes usage from
StorageGroup message and all related types
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
To encapsulate the complete information about the storage group in
StorageGroup message, this commit adds the missing group member list field.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
