owner/group of files in an aci is inconsistent

[slallema]

The files in the directory 'files' of a building dir for an aci are copied with the same owner and permissions. It should instead default to something like root + 0644 and we should provide a mechanism to override this like we have tomls for templates.

[n0rad]

user is now forced to root:root. Need a use case to go further

[n0rad]

The idea I have to solve it is to add a toml config file next to the file that defines the attributes if we want special transformation. I will probably do the same with the new templater