complete: Add support of rb completion (#2689)
complete: Add support of rb completion (#2689)

Add completion for rb command:
- Support filesystem paths
- S3 paths only supports this format: `alias/bucket/`, for that s3Complete{}
has deepLevel parameter to configure maximum path deep level.
minio/mc,krisis/mc,vadmeste/mc,balamurugana/mc,minio/mc,krisis/mc,vadmeste/mc,balamurugana/mc