error from 4.5 to 4.6 with cbrestore

Summary: Error message when using cbrestore

Repro: use cbrestore from a 4.5 backup to a 4.6 cluster.

Expected: backup to succeed

Actual: 

Exception in thread w0:
Traceback (most recent call last):
File "threading.pyc", line 551, in __bootstrap_inner
File "threading.pyc", line 504, in run
File "pump.pyc", line 303, in run_worker
File "pump_bfd.pyc", line 430, in get_conflict_resolution_type
IndexError: list index out of range

Notes: forum thread - https://forums.couchbase.com/t/couchbase-resotre/13131