use sed to get from one path to another rather than requesting it twice
use sed rather than pathof lookup in pack..by-dir.sh
write pathof into level 4 of request flags
fix writing file path into  level 4 of flag
use level 4 for pathof in packing scripts
fix filterDeleted

filterDeleted now uses [ -f ] test and also removes the flag file if the
original file does not exist.
add Cln command to create hardlinks
add cln to be created by scripts
first versions of IPython notebooks to install head and pool nodes
add ipython notebooks for dcache deployment