Create a way to add files from arbitrary filesystem locations

[blee]

There should be a way to add files from arbitrary filesystem locations. This facilitates using a "central" repository on a single machine without needing to login to target machines to import files.

For example, on machine foo you would like to add a file that should be installed in module bar as /usr/local/etc/confman.conf:

foo$ confman add bar /tmp/bar.conf /usr/local/etc/confman.conf