This promotion is controlled so that only a limited number a requests
are in the
state ToExpand or Starting at any point in time. This ensures both the
availabality
of repack file requests to system while preventing an explosion of file
level requests.

Created a one-round popping from the container (algorithms) with status
switching.
  - Used for repack requests switching from pendig to to expand

Added ElementStatus to algorithms.

Implemented promotion interface in Scheduler and OstoreDb. The actual
decision is taken at
the Scheduler level. The function itself is called by the
RepackRequestManager.

Promotion is tested in a unit test.

Various code maintenance:
Switched to "using"-based constructor inheritance.
Fixed privacy of function in cta::range.

Added partial support for repack queueing in scheduler database,
scheduler and CLI.

"ToTransfer" are to be picked up by tape sessions.
"ToReport" Includes both successes and failures to report, as the mechanism to report is the same.
   They will be handled by the reporter, which shares the single thread of the garbage collector.
"Failed" Will be a (possibly non-queue) container which will contain the failed requests. The operators
   will be able to examine, relaunch or abandon those requests.

The states and lifecycles of the requests have been reworked to reflect this lifecycle too.
The container algorithmes have been adapted to handle the multiple queue/container types.

The unit test is disabled as it does not pass yet.
Templated some structures to reflect imperfect similarities between inserting and popping.

Updated locking of ObjetOps in order to allow locking of sub-objects.
Make cta-objectstore-dump-object lockfree.

This will remove contention on the drive register as drives uipdate their statuses.
Also simplified structures in OStoreDB implementation (less references with added friend relations).

Replaced set_target_properties( .. .. INSTALL_RPATH ..) with set_property (TARGET .. APPEND PROPERTY INSTALL_RPATH ..)

In order to be efficient, the data (tape status and queue sizes) is cached in memory.
This function needed access to the catalogue (where the tape status is located).
This in turn required passing the catalogue object to:
 - The garbage colletion functions for all object types.
 - The garbage collector object now keeps a reference to the catalogue.
 - The path to the catalogue credential file should now be passed to cta-objectstore-collect-orphaned-object
 - The OStoreDB also needs a reference to the catalogue in order to queue retrive requests.

 The garbage collection member function are now also being passed a log context, so the requirement for better
 log of object fate can also be fulfilled later. This in turn required the passing of a logger object to
 the object store and relative helper classes.

 Finally, a dummy catalogue class has been created to be used in unit tests.

Created an objectstore utility for requeuing ArchiveRequests after deleting archive or retrieve queues.

This utility is to be used for cleaning up the pre-prod environement following a schema change in the archive queues.
It could support all object types on the long run, but currently only supports ArchiveRequests.

Created an objectstore utility cleaning up the root entry after deleting archive or retrieve queues.

This utility is to be used for cleaning up the pre-prod environement following a schema change in the archive queues.

Factored a first function out of OStoreDB into Herlpers.

Implemented Agent::garbageCollect()
Made AgentWatchdog fetch the timout from the agent object.
Fixed unconditional time tounter reset in AgentWatchdog::checkAlive()
Fixed missing log for garbageCollection.
Added utility (cta-objectstore-unfollow-agent) to mark agents as not followed when they get orphaned. This utility detects looping ownerships (two garbage coolectors watch each other and both die synchronously). This utility is not packaged.
Various log improvements.

Created a garbage collector subprocess for the drive daemon.
Created a AgentHeartbeat thread and added it to frontend, drive subprocess and GC subprocess.
Fixed logs and drive subprocess.
Renamed common/threading/Threading.[hc]pp to Thread.[hc]pp as there is only one class left in this file.

This new package contains the old makeMinimalVFS (renamed to cta-objectstore-initialize)
plus cta-objectstore-list and cta-objectstore-dump-object.

Agent becomes a usual class, like any other in the object store.
Object name generation (agent's and others) is now handled in the separate AgentReference.
The previous situation created race conditions.

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

The values are now hardcoded.
Cleanup:
  - Removed object store unit tests for data now in the catalogue.
  - Removed now unnecessary 2nd step addition of retry limits to archive jobs.
  - Removed deprecated ArchiveToFileRequest files.

Added binned running counters (ValueCoundMap) for managing summaries of priorities in object store queues.
Simplified the interfaces to the getPendingArchiveJobs and getPendingRetrieveJobs functions in Scheduler and SchedulerDB.
Removed now unused ArchiveToTapeCopyRequest.
Removed long unused mockScheduler.
Removed _old_protoype files.

Started morphing the code to accomodate both the move some data structure from OStoreDB to catalogue and shared structures modifications.
Renamed class members using underscode instead of mixed case.
Removed mount criteria from in-memory tape pool representation.
Removed support for path of archive files for in-memory representations.
Removed all but maxDrives allowed from in-memory representation of mount
policy.
Created new constructor for UserIdentity.
Switch the UserIdentity used by RemoteFileStatus.
Renamed TapePoolQueue to ArchiveQueue.
Replaced CreationLog usages with EntryLog.
Renamed TapeQueue to RetrieveQueue.
Removed support for data now gone to catalogue from RootEntry.
Removed corresponding structures from object store.
Removed corresponding calls from SchedulerDatabase and inheriting
classes (OStoreDB).