Move discovery to a console directory for contrib projects

[itsdarrylnorris]

Problem / Motivation

There seem to be some conflicts between some of the code organization between Drupal Console and Drupal Core and we should separate code. For instance, If you are building a generator for Drupal Console by default the templates are going to be store in /templates this is an issue for themes or for module that contain templates because is going to conflict.

Solution

Base on a conversation that I had with @jmolivas, we have decide to move all DrupalConsole code into sub-directory for Drupal Console called /console at the root directory of the contrib project.