Subsystem sftp internal-sftp and cd to $HOME
Subsystem sftp internal-sftp and cd to $HOME

- `Subsystem sftp internal-sftp` replaces legacy absolute path
  - https://serverfault.com/questions/660160/openssh-difference-between-internal-sftp-and-sftp-server#660325
- `ForceCommand internal-sftp -d %u` changes directory into
  /srv/ssh/jail/$user-name-ssh

atweiden/holovault