Update to php7.2

Author: jeckel

.travis.yml

@@ -10,7 +10,7 @@ before_script:
 
 script:
   - ./vendor/bin/phpunit --coverage-clover=coverage.xml
-  - ./vendor/bin/phpmd src text cleancode,codesize,design,naming,unusedcode
+  - ./vendor/bin/phpmd src text ./ruleset.xml
   - ./vendor/bin/phpcs
   - ./vendor/bin/psalm