Version 4.0.0 - Improve sync process and use the new INSEE API portal

This release completely changes the way the system update itself using the stock files.

Old update process

• Step 1: download zipped stock file
• Step 2: unzip stock file to a folder visible from the database
• Step 3: use COPY FROM in PostgreSQL to import the CSV file

New update process in 1 step

• connect a client to the stock file server supporting Ranges
• init the unzip library with the remote file
• stream the unzipped CSV in PostgreSQL

The new INSEE portal API is now used to do incremental updates during the month.