- Replaced the single user (so far defined in `/data/config.php`) with a multi-user management
  - The currently defined user will automatically be migrated, please remove `HTTP_USER` and `HTTP_PASSWORD` from your config file afterwards
  - For this it was necessary to delete all sessions and API keys during the migration
- Added an update script (`/update.sh`) to make updates (on Linux machines) easier
  - See also ["How to update" in README](https://github.com/berrnd/grocy#how-to-update)
- Added the possibility to track who did a habit
- Added a rudimentary habit analysis possibility
- Different small UI, code and translation improvements
