Upgrade dependencies to illuminate:5.6

Author: RemiCollin

composer.json

@@ -11,10 +11,10 @@
     ],
     "license" : "MIT",
     "require": {
-        "illuminate/support": "^5.5",
-        "illuminate/container": "^5.5",
-        "illuminate/database": "^5.5",
-        "illuminate/events": "^5.5",
+        "illuminate/support": "^5.6",
+        "illuminate/container": "^5.6",
+        "illuminate/database": "^5.6",
+        "illuminate/events": "^5.6",
         "mongodb/mongodb": "^1.0.0"
     },
     "require-dev": {
@@ -47,5 +47,7 @@
                 "Jenssegers\\Mongodb\\MongodbQueueServiceProvider"
             ]
         }
-    }
+    },
+    "minimum-stability" : "dev",
+    "prefer-stable": true
 }