minor #1376 Disable xdebug on travis (romainneutron)

This PR was submitted for the master branch but it was merged into the 1.3 branch instead (closes #1376).

Discussion
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Disable xdebug on travis

Commits
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2a4c4b39 Disable xdebug on travis

.travis.yml

@@ -6,6 +6,9 @@ cache:
     directories:
       - $HOME/.composer/cache
 
+before_install:
+    - if [[ $TRAVIS_PHP_VERSION != hhvm ]]; then phpenv config-rm xdebug.ini; fi
+
 before_script:
     # symfony/*
     - sh -c "if [ '$TWIG_VERSION' != '2.0' ]; then sed -i 's/~1.8|~2.0/~1.8/g' composer.json; composer update; fi"