Fix lowest dependencies

Tests/Export/ExporterTest.php

@@ -43,7 +43,8 @@ class ExporterTest extends \PHPUnit_Framework_TestCase
 
         $this->assertInstanceOf('Symfony\Component\HttpFoundation\Response', $response);
         $this->assertEquals($contentType, $response->headers->get('Content-Type'));
-        $this->assertEquals('attachment; filename="'.$filename.'"', $response->headers->get('Content-Disposition'));
+        // Quotes does not appear on some sonata versions.
+        $this->assertRegExp('/attachment; filename="?'.$filename.'"?/', $response->headers->get('Content-Disposition'));
     }
 
     public function getGetResponseTests()

composer.json

@@ -27,13 +27,15 @@
         "symfony/twig-bridge": "~2.3",
         "symfony/class-loader":"~2.3",
         "symfony/expression-language": "~2.4",
+        "symfony/property-access": "~2.3",
         "sensio/generator-bundle": "~2.3",
         "twig/twig": "~1.15",
         "twig/extensions": "~1.0",
         "sonata-project/exporter": "~1.0",
         "sonata-project/block-bundle": "~2.2,>=2.2.7,<2.3",
-        "sonata-project/core-bundle": "~2.2",
+        "sonata-project/core-bundle": "^2.2.1",
         "doctrine/common": "~2.2",
+        "doctrine/inflector": "~1.0",
         "knplabs/knp-menu-bundle": ">=1.1.0,<3.0.0",
         "knplabs/knp-menu": ">=1.1.0,<3.0.0"
     },