- Changed the smarty modifier poll_url to a function and added the vote_id parameter
	- Modified accordingly all poll_url occurence in templates
	- Added htaccess.txt to be sure to keep poll's URL changes up to date
	- Escaped some templates output in order to avoid to broke HTML
	- Using vote's uniqId instead of vote's id when it's needed

New files :
* classic_poll.js -> loaded on page choix_autre.php
* date_poll.js -> loaded on page choix_date.ph
* framadatepicker.js -> loaded on pages that need the date picker