Fix error with xdebug load

Author: redthor

.travis.yml

@@ -25,7 +25,7 @@ before_script:
   - if [[ "$COMPOSER_FLAGS" == *"--prefer-lowest"* ]]; then composer update --prefer-dist --no-interaction --prefer-stable --quiet; fi
   - composer update -v ${COMPOSER_FLAGS}
   # Restore xdebug for code coverage
-  - echo "extension=xdebug.so" >> ~/.phpenv/versions/$(phpenv version-name)/etc/php.ini
+  - echo "zend_extension=xdebug.so" >> ~/.phpenv/versions/$(phpenv version-name)/etc/php.ini
 
 script:
   - ./vendor/bin/phpunit --coverage-clover=coverage.clover