add traversal strategy parameter
add traversal strategy parameter

reneme/cvmfs,DrDaveD/cvmfs,djw8605/cvmfs,cvmfs-testing/cvmfs,MicBrain/cvmfs,cvmfs/cvmfs,Gangbiao/cvmfs,djw8605/cvmfs,djw8605/cvmfs,cvmfs/cvmfs,DrDaveD/cvmfs,cvmfs/cvmfs,trshaffer/cvmfs,reneme/cvmfs,trshaffer/cvmfs,cvmfs-testing/cvmfs,alhowaidi/cvmfsNDN,MicBrain/cvmfs,MicBrain/cvmfs,trshaffer/cvmfs,Moliholy/cvmfs,MicBrain/cvmfs,Gangbiao/cvmfs,alhowaidi/cvmfsNDN,Moliholy/cvmfs,trshaffer/cvmfs,Gangbiao/cvmfs,MicBrain/cvmfs,reneme/cvmfs,Moliholy/cvmfs,Gangbiao/cvmfs,cvmfs-testing/cvmfs,Moliholy/cvmfs,alhowaidi/cvmfsNDN,reneme/cvmfs,alhowaidi/cvmfsNDN,cvmfs/cvmfs,DrDaveD/cvmfs,Moliholy/cvmfs,trshaffer/cvmfs,DrDaveD/cvmfs,cvmfs/cvmfs,DrDaveD/cvmfs,cvmfs/cvmfs,reneme/cvmfs,Gangbiao/cvmfs,djw8605/cvmfs,djw8605/cvmfs,alhowaidi/cvmfsNDN,DrDaveD/cvmfs,cvmfs/cvmfs,DrDaveD/cvmfs,cvmfs-testing/cvmfs,cvmfs-testing/cvmfs