* unified the naming of .cat and .log files.
* Changed the name of output folder of pointing to corresponding pointing.obs_id. * fixed the order .cat hdr updating and the creation of .cat file. * Changed the naming of shutter and flat reference image: chip IDs now all in 2 digits. * Updated the __init__ method of ChipOutput * Removed Config.py from ObservationSim.Config * Cleaned codes in ObservationSim.py, ChipOutput