we need latest composer for travis

Author: dbu

.travis.yml

@@ -11,6 +11,7 @@ env:
   - SYMFONY_VERSION=dev-master
 
 before_script:
+  - composer self-update
   - composer require symfony/framework-bundle:${SYMFONY_VERSION} --prefer-source
   - cp ./Tests/Functional/config/parameters.yml.dist ./Tests/Functional/config/parameters.yml
   - php Tests/Functional/console doctrine:phpcr:init:dbal