Adds if statements to make travis work with hhvm

Author: nicholasruunu

.travis-php.ini

@@ -0,0 +1 @@
+extension = memcache.so

.travis.yml

@@ -13,11 +13,12 @@ matrix:
   fast_finish: true
 
 before_install:
-  - phpenv config-rm xdebug.ini
+  - sh -c 'if [ "$TRAVIS_PHP_VERSION" != "hhvm" ]; then phpenv config-rm xdebug.ini; fi;'
   - pip install --user codecov
 
 before_script:
-  - echo "extension = memcache.so" >> ~/.phpenv/versions/$(phpenv version-name)/etc/php.ini
+   # Need to activate memchache extension explictly to work with all versions.
+  - sh -c 'if [ "$TRAVIS_PHP_VERSION" != "hhvm" ]; then phpenv config-add .travis-php.ini; fi;'
   - travis_retry composer self-update
   - travis_retry composer install --prefer-source --no-interaction