Put the check-syntax script to work in the travis build. This resolves #361.

.travis.yml

@@ -10,7 +10,9 @@ matrix:
   allow_failures:
   - php: hhvm
 before_script: composer update --dev
-script: php vendor/phpunit/phpunit/phpunit.php --configuration tools/phpunit
+script:
+- php vendor/phpunit/phpunit/phpunit.php --configuration tools/phpunit
+- bin/check-syntax.sh
 after_success:
 - if [[ "$TRAVIS_PHP_VERSION" == "5.6" ]]; then php vendor/bin/coveralls -v; fi
 notifications: