rename 'label' to 'name'.

Warning : this commit require to rename some table column, but the
original Version file has been update.

If you do not care to loose your date, you may run :

```
php app/console doctrine:migrations:execute --down 20160318111334
php app/console doctrine:migrations:execute --up 20160318111334
php app/console doctrine:cache:metadata #(if you have a cache for
doctrine meta date)
```
close #20

Form/Type/TranslatableEventType.php

@@ -62,7 +62,7 @@ class TranslatableEventType extends AbstractType
                     ->where('et.active = true');
                 },
                 'choice_label' => function (EventType $t) use ($helper) {
-                    return $helper->localize($t->getLabel());
+                    return $helper->localize($t->getName());
                 },
             )
         );