adapt interface in libcvmfs.h for multi-repo support
adapt interface in libcvmfs.h for multi-repo support

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