Add hhvm

.travis.yml

@@ -5,17 +5,19 @@ php:
   - 5.6
   - 5.5
   - 5.4
+  - hhvm
 
 matrix:
   allow_failures:
     - php: nightly
 
-before_install:
+install:
   - npm install -g npm@latest
   - npm install -g bower gulp jscs
   - npm install
-  - pyrus install pear/PHP_CodeSniffer
-  - phpenv rehash
+  - composer self-update && composer --version
+  - export PATH="$HOME/.composer/vendor/bin:$PATH"
+  - composer global require squizlabs/php_codesniffer
 
 script:
   - npm run build