Harmonized the copyNb type to uint32_t
Corrected a bug in RetrieveQueue::getContainerSummary() --> After insertion in the queue, the number of files and bytes added were equal to 0.

The catalogue can receive polymorphic items as input for recording.
The strict sequencing of fSeqs is still enforced.
Currently, 2 items types are recorded: files and placehoders.
Files are recorded to the tape catalogue, while place holders are not,
but they are used to enforce the fSeq sequencing.

Done.

Removed deprecated structures from archiveNS and nameserver namespaces. Removed RetrieveToFileRequest.