Add verbose option to commands

Hey there!
As I've mentioned in #144, I've added `verbose` option to commands. It simply outputs all logs that normally are being saved into log files.
Usage is simple and quite customizable:

* you can use simply call any command with `--verbose` option:
```
mage deploy to:production --verbose
```
* you can also set verbose logging by default in `general.yml`:
```yml
name: My fantastic App
email: andresmontanez@gmail.com
notifications: true
logging: true
verbose_logging: false
```
* ... or for each environment separately:
```yml
#production
deployment:
  user: root
  from: ./
  to: /var/www/vhosts/example.com/www
  excludes:
    - application/data/cache/twig/*
releases:
  enabled: true
  max: 5
  symlink: current
  directory: releases
hosts:
  - s01.example.com
  - s02.example.com
tasks:
  pre-deploy:
    - scm/update
  on-deploy:
    - symfony2/cache-warmup: { env: prod }
    - privileges
    - sampleTask
    - sampleTaskRollbackAware
verbose_logging: true
```

Due to avoid messages duplication, when calling a command with `verbose`, messages normally called by `Console::output` (those coloured and intended ones) are hidden.
Thanks and looking forward for your feedback!