Simplified redundant code in symetric function for ArchiveMount.

Adjusted unit test to accomodate the new structure (SchedulerDatabase::RetrieveMount is now a pure virtual class).

Implemented cta::ArchiveJob::complete(), and added the members that should be set to have the necessary
information available at complete() time.
Updated the calls in the archive_and_retrieve_new_file unit test.

Please note that this test does not pass because the functionality
being tested has not yet been implemented.

Fixed DataTransferSessionTest. Still needs some tuning to make the last tests meaningful, but we need to have the first ones working first (which will take time).

Added full emulation of a tape session in the archive_and_retrieve_new_file unit test for the scheduler.
Fixed several bugs.

Removed usage of the mock scheduler database that will not be updated for further modification in the scheduler database interface.

Added getting the per tape status in objectstore::TapePool::dumpTapes() (renamed to objectstore::TapePool::dumpTapesAndFetchStatus()).
Implemented the mount selection logic for archives in Scheduler::getNextMount().

The uncommented tests of DataTransferSessionTest now create tape file entries in the archive namespace

bridge constants, therefore this commit renames:

  castor/tape/tapeserver/Constants.hpp

to:

  castor/tape/tapeserver/TapeBridgeConstants.hpp.

PLEASE NOTE:
Both the DataTransferSessionGooddayRecall and DataTransferSessionWrongRecall
tests have TODO comments that need to be fleshed out into real code.  More
specifically both tests need to fill the archive namespace with tape file
entries reflecting what was written to the in the memory tape of each unit
test.

Added suport for both failure and success for the OStoreDB::ArchiveJob() and tested the job's basic requeuing on failure.