Added support for retrieve failure reporting to EOS.

common/dataStructures/RetrieveRequest.hpp

objectstore/ArchiveRequest.cpp

objectstore/ArchiveRequest.hpp

objectstore/RetrieveRequest.cpp

objectstore/RetrieveRequest.hpp

objectstore/cta.proto

scheduler/OStoreDB/OStoreDB.cpp

scheduler/OStoreDB/OStoreDB.hpp

scheduler/RetrieveJob.cpp

scheduler/RetrieveJob.hpp

scheduler/RetrieveMount.cpp

scheduler/RetrieveMount.hpp

scheduler/Scheduler.cpp

scheduler/SchedulerDatabase.hpp

scheduler/testingMocks/MockRetrieveJob.hpp

...rver/castor/tape/tapeserver/daemon/RecallReportPacker.cpp

.../castor/tape/tapeserver/daemon/RecallReportPackerTest.cpp

xroot_plugins/XrdSsiCtaRequestMessage.cpp