MB-10263: export revid in csv format

Change-Id: Id4f54da6b94d2682aa0cd8a8abfcfb014c54dd63
Reviewed-on: http://review.couchbase.org/34583
Reviewed-by: Bin Cui <bin.cui@gmail.com>
Tested-by: Bin Cui <bin.cui@gmail.com>