Lets a candidate be marked ignored instead of confirmed/applied; future
scans skip re-flagging the same path pair once it's been ignored, since
a rescan can flip which side ranks as keep/delete without changing the
user's earlier decision that the pair is fine as two copies. Also adds
--apply-pairs to find-fuzzy-dupes.py to apply pre-confirmed pairs
without a full rescan.
andrew
9d1eee3337