Functionality for PUID/PGID

[coanghel]

Description

This might be user error but I can't figure out a good way to have this container not make the contents of /data/ owned by root. This is just a bit of a pain if I want to, for example, SFTP drop new .local or .conf files rather than sudo vi them in place.

For now, I'm just chown-ing the files after the container initializes but that feels wrong...