Update composer.json

Author: barryvdh

composer.json

@@ -11,10 +11,10 @@
     ],
     "require": {
         "php": ">=5.5.0",
-        "illuminate/support": "5.3.x|5.4.x|5.5.x",
-        "symfony/form": "^3",
-        "symfony/validator": "^3",
-        "symfony/twig-bridge": "^3",
+        "illuminate/support": "5.5.x|5.6.x",
+        "symfony/form": "^3.4",
+        "symfony/validator": "^3|^4",
+        "symfony/twig-bridge": "^3|^4",
         "twig/twig": "~1.30|~2.0"
     },
     "autoload": {
@@ -29,7 +29,7 @@
     },
     "extra": {
         "branch-alias": {
-            "dev-master": "0.3-dev"
+            "dev-master": "0.4-dev"
         },
         "laravel": {
             "providers": [