Send Code Coverage reports to Coveralls

References:
javiereguiluz/EasyAdminBundle@0f0b268
https://github.com/satooshi/php-coveralls

.coveralls.yml

@@ -0,0 +1,3 @@
+service_name: travis-ci
+src_dir: .
+coverage_clover: build/logs/clover.xml

.travis.yml

@@ -28,8 +28,12 @@ before_install:
   - composer self-update || true
   - if [ "$TRAVIS_PHP_VERSION" != "hhvm" ]; then echo "memory_limit = -1" >> ~/.phpenv/versions/$(phpenv version-name)/etc/conf.d/travis.ini; fi
   - if [ "$SYMFONY_VERSION" != "" ]; then composer require --no-update symfony/symfony=$SYMFONY_VERSION; fi;
+  - if [[ $TRAVIS_PHP_VERSION = '7.0' && $SYMFONY_VERSION = '2.8' ]]; then composer require --no-update "satooshi/php-coveralls:~0.6"; PHPUNIT_FLAGS="--coverage-clover ./build/logs/clover.xml"; else PHPUNIT_FLAGS=""; fi
 
 install:
   - composer update $COMPOSER_FLAGS --prefer-source
 
-script: php ./vendor/bin/phpunit
+script: php ./vendor/bin/phpunit $PHPUNIT_FLAGS
+
+after_success:
+ - if [[ $PHPUNIT_FLAGS != "" ]]; then travis_retry php vendor/bin/coveralls -v --config .coveralls.yml; fi