Added the retryable error exception and added the catching of different backend exceptions in the frontend

Implementation of the top level retrieve request queueing in Scheduler.

Renamed drData (and its fields) to diskFileInfo to better reflect the use that we make of that structure

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

Added comments in the EOS interface doc.\nRenamed MountGroup into MountPolicy and removed MountPolicy (adapted SQL code).\nRemoved amount of data to warrant a mount from LogicalLibrary.

Added last update time in the ArchiveFile and split the updatefileinfo command in two: updatefileinfo (run by EOS during resynchronization process) and updatefilestorageclass (run by EOS on behalf of a user who wants to change the storage class of a file)

Changed the documentation fro the eos interface and the instance crosstalk, renamed User into Requester, refactored all the SQLITE code to have a GROUPNAME column in the requester, changed the tests

removed the minqueued bytes and files from mountgroup and mountpolicy. added minqueued bytes to logical library

processes. The socket transmits and queues variable size messages.

added to the interfaces the features requested by Vlado: label/lastwrite/lastread logs, encryption key and lbp tag for tapes; and encryption flag for pools

The contents of the Utils.cpp file is a namespace and not a class
therefore the file should start with a lower case letter.

Created an StdoutLogger class.
Created a CommandLineParams class that will allow early parsing, before the daemon object is actually created.

Removed unused cmake directory.
Added missing reset to getopt's global variables.
Fixed missing inclusion of unit test.
Fixed code that failed in unit tests.