+ Simplify call to remove all votes of one poll

* Use Smarty to split View and Controller on studs page (work in progress)
* Add field "active" to Poll
* And some other stuff...

* Utils::issetAndNoEmpty is now removed
* Use Form object to store value from page to page

* Rename fields in Sondage table
* Add field "editable" which tells when users can edit their votes
* PDO : Configure 2 options (FETCH_OBJ + ERRMODE_EX)
* "formatsondage" does contains "+" (or not) anymore

* Store all informations about forms into an object "Form" stored in $_SESSION['form']
* Replace connection to database by PDO object
* Check if database is ready in bandeaux.php file

condition is based on the number of languages configured

bug correction on email notification (using '$dsondage->titre' in adminstuds.php)

deplace config.inc.php file from root to app/inc dir. Allow access from anywhere and not only from a file present in root dir.

Modification des appels de function.inc.php (ajout dans init) pour être accessible par toutes les pages