Remove ComposerRequireChecker

Author: ondrejmirtes

.travis.yml

@@ -11,6 +11,3 @@ before_script:
   - if [ "$dependencies" = "highest" ]; then composer update --no-interaction; fi;
 script:
   - vendor/bin/phing
-  - >
-    wget https://github.com/maglnet/ComposerRequireChecker/releases/download/0.2.1/composer-require-checker.phar
-    && php composer-require-checker.phar check composer.json