Add more user indications

In Using_notebooks.ipynb

Add a section at the end:

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to download your data and results:

open the terminal and go to the working directory

cd /data/visitor/hg159/id13

and type

source ftptools.sh

to transfer your data to the ESRF ftp server

ftpshare your_data your_tmp_folder/.

You can access your data in http://ftp.esrf.fr/tmp/

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In 2_integration_maps.ipynb

Put by default

reference = calibrant.CALIBRANT_FACTORY("hydrocerussite.D")