Travis: remove phpcpd

No need for this to be part of continuous integration.

.travis.yml

@@ -17,15 +17,11 @@ notifications:
 before_script:
   # PHP_CodeSniffer
   - curl -L -o phpcs.phar https://squizlabs.github.io/PHP_CodeSniffer/phpcs.phar
-  # PHP Copy/Paste Detector
-  - curl -L -o phpcpd.phar https://phar.phpunit.de/phpcpd.phar
   # Basic config required for PHPUnit
   - cp qa-tests/phpunit-qa-config.php qa-config.php
 
 script:
   # PHP_CodeSniffer
   - php phpcs.phar --report=emacs --extensions=php --standard=qa-tests/phpcs/ruleset.xml .
-  # PHP Copy/Paste Detector
-  - php phpcpd.phar --exclude vendor .
   # PHPUnit
   - phpunit --bootstrap qa-tests/autoload.php qa-tests