client: UUIDIterator now allows to be redirected to a replica which is not...

client: UUIDIterator now allows to be redirected to a replica which is not known yet. (Needed for operations like mkfs.xtreemfs which are executed on a slave and do redirect to the master). Works for UUIDs and addresses which are stored in UUIDIterator.

git-svn-id: https://xtreemfs.googlecode.com/svn/trunk@2603 f8528748-c2c0-11dd-ba5c-d3b7c2b3b534