Zstage2nxs output filename templated flexibility for managing output in workflow

Ability to redirecte output to a suited directory and with adapted filenames. Using output_filename_template option

• Example of usage :

 nxtomomill zstages2nxs \\\
 --output_filename_template sessionIN1173_Bliss2NxMultiZScript_output_dir/sessionIN1173_Bliss2NxMultiZScript_output_XXXX.nx \\\
 --filename_template /data/visitor/in1173/bm18/20230711/RAW_DATA/HA1000_25.54um_smartiso_XXXX/in1173_HA1000_25.54um_smartiso_XXXX.h5 \\\
 --entry_name entry0000 \\\
 --total_nstages 35 \\\
 --first_stage 0 \\\
 --last_stage 5 \\\
 --do_references True \\\
 --ref_scan_begin /data/visitor/in1173/bm18/20230711/RAW_DATA/HA1000_25.54um_smartiso_REF_B/in1173_HA1000_25.54um_smartiso_REF_B.h5 \\\
 --ref_scan_end /data/visitor/in1173/bm18/20230711/RAW_DATA/HA1000_25.54um_smartiso_REF_B/in1173_HA1000_25.54um_smartiso_REF_B.h5