- remove 12.0 migration scripts
- bump version to 16.0
- use new api convention @api.model_create_multi ; new compute function logic ;
- add dependency to spreasheet_dashboard to use 'Dashboard' main menu item
- use new way to include assets
- remove totally useless controllers
- distinct different errors, depending on domain or format errors
- fix : _compute_data depends on many fields
- update : documentation and printscreens