Change the output from the scan action to be a HandBrake::Disc
object which contains a titles hash, rather than the hash directly.
When scanning for a single title, return only a single
HandBrake::Title.
Accept a path for the :atomic option to
HandBrake::CLI#output. If specified, the temporary file will be
written to this path rather than the ultimate target directory.
Ensure that trace mode prints updating lines (e.g., the encode
status) that do not end in newlines in a timely fashion.