replace some entity shortcut by fqdn

* ChillPerson:Person
* ChillMain:Center
* ChillActivity:Activity

src/Bundle/ChillMainBundle/Command/SetPasswordCommand.php

@@ -43,7 +43,7 @@ class SetPasswordCommand extends Command
     public function _getUser($username)
     {
         return $this->entityManager
-            ->getRepository('ChillMainBundle:User')
+            ->getRepository(\Chill\MainBundle\Entity\User::class)
             ->findOneBy(['username' => $username]);
     }