Done (replication preparation).

git-svn-id: https://svn.erp5.org/repos/neo/trunk@2334 71dcc9de-d417-0410-9af5-da40c76e7ee4

TODO

@@ -109,10 +109,6 @@ RC  - Review output of pylint (CODE)
       replication should happen independently of cluster state. (Maybe we still
       need a primary master, to void replicating from an outdated partition
       table setup.)
-    - Close connections to other storage nodes (SYSTEM RESOURCE USAGE)
-      When a replication finishes, the connection is not closed currently. It
-      should be closed (possibly asynchronously, and possibly by detecting that
-      connection is idle - similar to keep-alive principle)
     - Notify master when storage becomes available for clients (LATENCY)
       Currently, storage presence is broadcasted to client nodes too early, as
       the storage node would refuse them until it has only up-to-date data (not