split out file to scroll mapping

Signed-off-by: Mattias Andrée <maandree@operamail.com>
update documention style documentation

Signed-off-by: Mattias Andrée <maandree@operamail.com>
split out changing from path to id and discarding of unclaim superpaths when finding file owners

Signed-off-by: Mattias Andrée <maandree@operamail.com>