First version of expandRepackRequest + unit test

common/CMakeLists.txt

common/dataStructures/RetrieveFileQueueCriteria.cpp

common/dataStructures/RetrieveFileQueueCriteria.hpp

common/dataStructures/RetrieveRequest.cpp

common/dataStructures/RetrieveRequest.hpp

objectstore/RetrieveRequest.cpp

objectstore/RetrieveRequest.hpp

objectstore/cta.proto

scheduler/Scheduler.cpp

scheduler/Scheduler.hpp

scheduler/SchedulerTest.cpp