Update travis and coveralls

Author: j.guyon

.coveralls.yml

@@ -1,3 +1,2 @@
-service_name: travis-ci
-src_dir: .
 coverage_clover: build/logs/clover.xml
+json_path: build/logs/coveralls-upload.json

composer.json

@@ -29,7 +29,6 @@
     },
     "require-dev": {
         "phpunit/phpunit": "^5.7",
-        "phpunit/phpcov": "^3.1",
         "php-coveralls/php-coveralls": "^2.0",
         "doctrine/doctrine-fixtures-bundle": "^3.0.0",
         "liip/functional-test-bundle": "^1.9",