Use V4 ('s3v4') signature version for for all presigning URLs to support
backblaze, fixes#2472
- add 'access_addressing_style' to be able to choose virtual/path
addressing for access endpoint (default to 'virtual' as before)
- fix minio presigning with v4 by using 'path' addressing style for
minio
- if path matches '/data/' for internal minio bucket, then always use
'path'
- also make minio access path '/data/' configurable
also simplify running in any namespace with default settings:
- don't hardcode 'local-minio.default'
- in crawlers namespace, add a 'local-minio' externalName service which
maps to the main namespace service.
f1fd11c031