Merge branch '2.7' into 2.8

* 2.7:
  Add missing conflict rules for phpunit

Author: nicolas-grekas

composer.json

@@ -33,6 +33,7 @@
         "symfony/translation": "^2.0.5|~3.0.0"
     },
     "conflict": {
+        "phpunit/phpunit": "<4.8.35|<5.4.3,>=5.0",
         "symfony/doctrine-bridge": "<2.7",
         "symfony/framework-bundle": "<2.7",
         "symfony/twig-bridge": "<2.7"