Merge pull request php-debugbar#241 from GrahamCampbell/patch-2

Use PSR-4 without moving files about

Author: barryvdh

composer.json

@@ -19,7 +19,9 @@
         "phpunit/phpunit": "^4.0|^5.0"
     },
     "autoload": {
-        "psr-0": {"DebugBar": "src/"}
+        "psr-4": {
+            "DebugBar\\": "src/DebugBar/"
+        }
     },
     "suggest": {
         "kriswallsmith/assetic": "The best way to manage assets",