0.27.0

This release...

1. ...drops some BOSH properties:
   • grootfs.external_logdevice_size_in_mb which refers to the ability to use a separate loop device for the XFS log.
   • grootfs.persistent_image_list and grootfs.store_size_bytes: both in dropped in favour of the new cache management approach which will be governed by grootfs.cache_size_bytes and a sensible default.
2. ...improves the security of the set-UID binary which is used by the Overlay-XFS driver (tardis) when GrootFS is used in rootless mode.
3. ...introduces grootfs.experimental_rootless_mode which is linked to Garden's respective BOSH property. NOTICE: If you have garden.experimental_rootless_mode turned on, you will need to recreate your Diego Cells.
4. ...allows root use to consume GrootFS even if the helper binaries (drax and tardis) are not set-UID.
5. ...enables GrootFS to download remote layers from an mTLS HTTP store.