update travis settings

Author: mikaelcom

.travis.yml

@@ -20,7 +20,7 @@ install:
     - composer install
 
 script:
-    - ./vendor/phpunit/phpunit/phpunit --coverage-text --coverage-clover=coverage.clover
+    - ./vendor/bin/phpunit --coverage-text --coverage-clover=coverage.clover
 
 after_script:
     - wget https://scrutinizer-ci.com/ocular.phar