Fix travis builds.

Travis updated to phpunit 4 for PHP 5.3 and CakePHP needs phpunit 3.7.

.travis.yml

@@ -18,6 +18,8 @@ matrix:
         - PHPCS=1
 
 before_script:
+  - sh -c "if [ '$TRAVIS_PHP_VERSION' != '5.2' ]; then composer global require 'phpunit/phpunit=3.7.33'; fi"
+  - sh -c "if [ '$TRAVIS_PHP_VERSION' != '5.2' ]; then ln -s ~/.composer/vendor/phpunit/phpunit/PHPUnit ./vendors/PHPUnit; fi"
   - sudo locale-gen de_DE
   - sh -c "if [ '$DB' = 'mysql' ]; then mysql -e 'CREATE DATABASE cakephp_test;'; fi"
   - sh -c "if [ '$DB' = 'mysql' ]; then mysql -e 'CREATE DATABASE cakephp_test2;'; fi"