Phpunit - fix

For more information, see:
sebastianbergmann/phpunit#1265

Author: Pedro Amorim

phpunit.xml.dist

@@ -13,7 +13,7 @@
          stopOnFailure="false"
          stopOnIncomplete="false"
          stopOnSkipped="false"
-         testSuiteLoaderClass="PHPUnit_Runner_StandardTestSuiteLoader"
+         testSuiteLoaderFile="./vendor/phpunit/phpunit/PHPUnit/Runner/StandardTestSuiteLoader.php"
          strict="false"
          verbose="false">
     <testsuites>