Overhaul of docker-laravel-starter Project #17

A lot has changed since I shipped Docker for PHP Developers and the accompanying starter project.

While I think the starter project still provides a good reference to starting to use Laravel with Docker, I think the starter bundle could be improved. I would like to include the following in the updated version:

• Upgrade to the latest Laravel version
• Improve the documentation
• Add configuration for dynamic PHP-FPM child process settings
• Include PHPRedis support
• This work should try to solve concerns raised in docker-laravel-starter-master #14 about running in production
• Sets the stage for an upcoming module: extracting to a reusable base image