Install Global Composer Packages

You now add composer packages to a variable in the vagrant file to install packages like: phpunit and codeception.
Delete phpunit.sh as it's replaced with composer_packages.sh
Moved composer_packages.sh into composer.sh
Adding a vhost script for nginx into the repo rather than in a gist so it can be managed as part of the main repo.
Adding Supervisor support
Merge pull request #83 from seandowney/develop

Adding a vhost script for nginx
Merge pull request #81 from Ilyes512/global_composer_packages

Global composer packages