Update composer.json: renommage package + suppression clé repositories inutile.

composer.json

 {
-    "name": "unicaen/unicaen-zimbra",
+    "name": "unicaen/zimbra",
     "description": "Module de pilotage de Zimbra de l'UCBN",
-    "repositories": [
-        {
-            "type": "composer",
-            "url": "http://dev.unicaen.fr/packagist"
-        }
-    ],
     "require": {
     },
     "require-dev": {