- corrected security issue in config page and reorganized code for better readability

- prepared base and interface to handle multiple users

- INCOMPLETE started working on the 'create user' functionality
- 'add/edit user' forms are now working

- new users can log in (for now everyone has access to everything)
closed access to config for lambda users except for the 'change password' functionality
- handle association between users and dreamers

- restrict write dream for dreamers linked to current user (except admins)
auto-select a dreamer name in the dream form if it is close to the current user name (using levenshtein distance) and if it isn't already selected
sanitize all strings on user input via htmlspecialchars (including the csv file)
added a little javascript to avoid accidentaly leaving the dream form and losing all entered information
avoid double encoding on import from exported file
added authorship to dreams (only via import for now)
- added dream authorship in dream form

- restricted access to dream edition/deletion for author and admins

- error handling for user without any dreamer

- corrected a bug in the use of levenshtein distance
ability to reassign every dream of a dreamer to a user (useful after a CSV import)
small correction on warning display
- FIX: encoding problem on tags during import due to unnecessary lowercase transformation

- emptying the link between dreamers and users when deleting dreamers on import
added a warning message for CSV import
- multiple FIX on import/export of tags and author

- added an 'app key' for the public RSS feed, to avoid unwanted access
FIX dream always saved with newly created empty dreamer
FIX broken sort order on dream list (including RSS and CSV)
FIX backward compatibility importing CSV files with tags
changed the sort order for dreams on index page as discussed with BoboTig: make the order work for tons of imported dreams and also for manually created dreams
FIX on user config page, dreamer checkbox list prechecked items