update usage

src/create_users_from_user_pwd_list.sh

 #! /usr/bin/bash
 
 # USAGE
-# upload create_users_from_user_pwd_list.sh and user_pwd_list.tsv
-# bash create_users_from_user_pwd_list.sh user_pwd_list.tsv
+# wget https://gitbio.ens-lyon.fr/can/R_basis/-/raw/master/src/create_users_from_user_pwd_list.sh
+# upload X_user_pwd_list.tsv from your computer to the rstudio server
+# sudo bash create_users_from_user_pwd_list.sh X_user_pwd_list.tsv
 
 USER_PASSWORD_FILENAME=$@
 while IFS=$'\t' read -r GROUPE NAME SURNAME MAIL LOGIN_CBP PASSWD_CBP LABO R_USERNAME R_PASSWD ; do