Allow individual bridges, bundles and components to be used with 4.0

Author: dunglas

composer.json

@@ -17,14 +17,14 @@
     ],
     "require": {
         "php": ">=5.5.9",
-        "symfony/http-kernel": "~2.8|~3.0",
-        "symfony/twig-bridge": "~2.8|~3.0",
-        "symfony/var-dumper": "~2.8|~3.0"
+        "symfony/http-kernel": "~2.8|~3.0|~4.0.0",
+        "symfony/twig-bridge": "~2.8|~3.0|~4.0.0",
+        "symfony/var-dumper": "~2.8|~3.0|~4.0.0"
     },
     "require-dev": {
-        "symfony/config": "~3.3",
-        "symfony/dependency-injection": "~3.3",
-        "symfony/web-profiler-bundle": "~2.8|~3.0"
+        "symfony/config": "~3.3|~4.0.0",
+        "symfony/dependency-injection": "~3.3|~4.0.0",
+        "symfony/web-profiler-bundle": "~2.8|~3.0|~4.0.0"
     },
     "suggest": {
         "symfony/config": "For service container configuration",