Removes Redis implementations

I removed several classes that provide Redis implementations directly
in the child Sonido namespaces and moved them into a Sonido\Redis
namespace.

Changed a few class names/interfaces to be more consistent.
Fixed Stat interface

Turned this into an actual interface instead of a class.
Code cleanup + Spork

Did some code cleanup and also added in the Spork library to
composer.json and registered it with the DI container.
Initial Symfony Console app

This is the initial Symfony Console app implementation. I started a
new, "sonido2" file for now, so that we can continue to reference the
old one until this one is complete.

Still needs to be finished, since it doesn't actually execute jobs yet
- should be easy enough though.