Merge branch '2.8' into 3.2

* 2.8:
  Add missing conflict rules for phpunit

Author: nicolas-grekas

composer.json

@@ -59,7 +59,8 @@
     },
     "conflict": {
         "phpdocumentor/reflection-docblock": "<3.0",
-        "phpdocumentor/type-resolver": "<0.2.0"
+        "phpdocumentor/type-resolver": "<0.2.0",
+        "phpunit/phpunit": "<4.8.35|<5.4.3,>=5.0"
     },
     "suggest": {
         "ext-apcu": "For best performance of the system caches",