Pass clientuuid on RawFileStoreI.__redirect

Without the client's uuid, it's not possible for
setFileId to be called.
Provide clientUuid in ManagedImportRequestI
Refactor log/annotation methods for concurrency

The mix of internal (ome.model) and external (omero.model)
calls in ManagedImportRequestI was leading to strange
concurrency issues. By moving all of the calls into
essentially other transactions, this should be resolved.
Use IUpdate for size update rather than RFS

Despite the work on the clientUuid, use of RFS with
repo files is still not viable in this use case because
a default of "r" is used by Repository.fileById. Rather
than introduce an "omero.rfs.write" context variable at
this point, we're just using IUpdate.