Added Vagrant configuration cookbook

| Q             | A
| ------------- | ---
| Doc fix?      | no
| New docs?     | yes
| Applies to    | all
| Fixed tickets | n/a

A new cookbook article was added with an example Vagrant configuration that can be used with the Symfony Standard Edition.
Ya, I do something similar when I am debugging with a browser.  The comments I posted were more related to command line debugging, like when I'm debugging a PHPUnit test or a Symfony Command class.