Update composer.json
Added branch alias
Merge pull request #44 from GrahamCampbell/composer

Update composer.json
Install PHPCS via Composer.
Let HHVM run FREEEEEE.
Attempt new code coverage approach.
Fixing test for HHVM Build
Merge pull request #46 from Gufran/fix/hhvm-test-fix

Fixing test for HHVM Build
Implementation of configurable serializers.

Signed-off-by: Jason Lewis <jason.lewis1991@gmail.com>