Discus test
Ajout de la librairies HybridAuth

Cette librairies permet de gérer des authentifications distantes (oauth)
tel que twitter, facebook etc...
Add a singleton pdo library.
Include pdo library in the header.
Merge branch 'mysql_handler' into 2.0.0

Conflicts:
	application/donnees-liberees-chercheurs-debrides-societe-impliquee.php