[WIP] Key replacements on the shard range

BugzId: 20423
[WIP] Update changes coordinator

BugzId: 20423
[WIP] updated stream_start
[WIP] updated changes
[WIP] updated map
[WIP] revert fabric_view_changes changes
[WIP] stream start update
[WIP] new fabric_view:get_shard_replacements/2
[WIP] fabric view map update
[WIP] fabric view reduce update
[WIP] the real changes update
[WIP] stuff