Added options, suppressions and re-implemented BackendVFS::AsyncLockfreeFetcher to try and make valgrind happy.

Proceed all successful reports asynchronously and periodically check
and clear statuses if they have finished.
In the end of session do the check/flush for all reports in the
successful reports queue.

Switch from synchronous rados remove to async aio_remove in
case of zero size object in BackendRados::AsyncUpdater

Fixed calls to promise::get_future() after possible access form other thread. They are now guaranteed to happen before.
Added helgrind annotations for promise based synchronisation.
Added macros enabling helgrind annotations for shared_ptr.
Added suppression for shared_ptr used inside other standard lib object and not covered by the previous macros.
Added unit test for lower level .
Added suppressions for reported race conditions in Rados library.
Review heavily MemArchiveQueue and fixed missing commit in object store, leading to potentially orphaned objects.
Enabled formerly disabled test as it is now fast enough.

This is done by replacing unique_ptr/bare pointer with 2 shared_ptr.
Also added suppressions for helgrind complains about rados.

Added mechanism to make sure the ArchiveQueue lock is released only after all requests
have had their ownership updated.

Increased queue depth in helgrind reports.
Added locking in a constructor to make helgrind happy.
Added suppression for helgrind finding races in synchronization functions (?)

This was a slight variation of the previous case (again a complain on mutex_destroy).

https://st-ci.cern.ch/job/CTA-autotest/1034/consoleFull

The first 6 issues are about places where error conditions of the pthread mutexes are validated (And a suppression is required).
The 7th one is about a race between the unlocking of the mutex itself and it deletion. We seupresed this error also.

Replaced castor file header with CTA file header

Moved castor::server::
  BlockingQueue
  Semaphores
  AtomicCounter
  AtomicFlag
into cta::threading::

Fixed spurious file closing on failure to open in BackendVFS.

Added new make targets for helgrind and valgrind.