Subdirectories in user-jail don't contain correct permissions.

[KilianDargel]

When pushing to the sftp server as a user to subdirectories, they are not allowed to push anything by default.
Although sftp-server-pods have a long lifetime, they sometimes need to be manually "prepared" - making them non-stateless - like so:

/ # mkdir home/<user>/<subdirectory1>
/ # mkdir home/<user>/<subdirectory1>/<subdirectory2>
...
/ # chown -R roamcontrol:100 home/<user>/<subdirectory1>/

I suggest a mechanism that sets up the FS through containerscripting like above. The chart currently carries a KV sftpConfig.username so how about a range for sftpConfig.userdirectories?
e.g.:

sftpConfig:
   username: sftp
   userdirectories:
   - subdirectory1/subdirectory2
   - subdirectory3

[sj14]

This patch #11 also seems to fix the missing permissions.