Partial implementation of the retrieve queue handling in object store.

common/CMakeLists.txt

common/dataStructures/RetrieveRequest.cpp

common/dataStructures/RetrieveRequest.hpp

common/dataStructures/TapeFile.hpp

common/exception/NonRetryableError.cpp

common/exception/NonRetryableError.hpp

objectstore/ArchiveQueue.cpp

objectstore/ArchiveQueue.hpp

objectstore/ArchiveRequest.cpp

objectstore/ArchiveRequest.hpp

objectstore/BackendPopulator.cpp

objectstore/DiskFileInfoSerDeser.hpp

objectstore/DriveRegister.cpp

objectstore/DriveRegister.hpp

objectstore/EntryLogSerDeser.hpp

objectstore/GarbageCollectorTest.cpp

objectstore/MountPolicySerDeser.hpp

objectstore/RetrieveQueue.cpp

objectstore/RetrieveRequest.cpp

objectstore/RetrieveRequest.hpp