doc: document hadoop replication config

Signed-off-by: Noah Watkins <noahwatkins@gmail.com>
doc: fix command syntax

Signed-off-by: Noah Watkins <noahwatkins@gmail.com>
Merge remote-tracking branch 'origin/wip-hadoop-docs'

Signed-off-by: Noah Watkins <noahwatkins@gmail.com>