This SR is intended to be used in a demo next week. The purpose is to have a running pureftpd server which will call a script "/opt/pureftpd/upload_script" each time a file is uploaded. Pureftpd is used because it is already used in the current working environment of our partner and they don't want to change for now.

The script /opt/pureftpd/upload_script" is left out of the SR on purpose because it will be written by people outside Nexedi at first and contains sensitive information. Also, it is on purpose in /opt directory of the machine because this SR will be deployed on only one machine for now and the script will be shared by all pureftpd instances.

We don't merge this MR yet as we don't really know if this SR will be useful later...

/cc @jm @jerome