Ticket 49287 - v3 extend csnpl handling to multiple backends
The csn pending list mechanism failed if internal operation affected multiple backends
This fix is an extension to the fix in ticket 49008, the thread local data now also contains
a list of all affected replicas.
http://www.port389.org/docs/389ds/design/csn-pending-lists-and-ruv-update.html
Reviewed by: William, Thierry - thanks