Removed mocking of classes where functions have non-copyable argumentes (unique_ptr).
Replaced NULL references to watchdogs to dummies where necessary.

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.

NOT ALL OF THE TAPEDAEMON UNITTESTS ARE BEING COMPILED AND THERE ARE
STILL UNITTESTS THAT ARE COMPILED THAT DO NOT PASS

Renamed CTA/tapeserver/castor to CTA/tapeserver/castor_checkout in preparation for the moving the sub-directory CTA/tapeserver/castor/castor up the directory tree