When we have cgo, use fgetpwent() to try to look up user IDs and primary
GIDs in containers. If that fails for any reason (or if we don't have
cgo), fall back to doing what we were doing before (i.e., trying to look
up the information on the host).
Signed-off-by: Nalin Dahyabhai <nalin@redhat.com>
Closes: #63
Approved by: rhatdan
