Support Laravel for PHP users

Reposting suggestion from conversation in Slack about adding support for using Pyroscope with Laravel:

1. add a pyroscope scope to https://github.com/laravel/sail/tree/1.x/stubs
2. make it easy to run laravel with pyroscope

A development server can be started with php artisan serve
Maybe you could a a flag that looks something like: php artisan serve --pyroscope

References:
- https://www.blackfire.io/
- https://laravel.com/docs/8.x/scout