"This series switches repair to use more stream plans to stream the mismatched
sub ranges and use a range generator to produce sub ranges.
Test shows no huge memory is used for repair with large data set.
In addition, we now have a progress reporter in the log how many ranges are processed.
Jun 06 14:18:22 [shard 0] repair - Repair 512 out of 529 ranges, id=1, keyspace=myks, cf=mytable, range=(8526136029525195375, 8549482295083869942]
Jun 06 14:19:55 [shard 0] repair - Repair 513 out of 529 ranges, id=1, keyspace=myks, cf=mytable, range=(8526136029525195375, 8549482295083869942]
Fixes #2430."
* tag 'asias/fix-repair-2430-branch-master-v1' of github.com:cloudius-systems/seastar-dev:
repair: Remove unused sub_ranges_max
repair: Reduce parallelism in repair_ranges
repair: Tweak the log a bit
repair: Use more stream_plan
repair: iterator over subranges instead of list
(cherry picked from commit 419ad9d6cb)
