add ability to see puppet debug log via env
add ability to see puppet debug log via env

This makes debugging rspec tests a little easier by providing the
ability to capture the puppet debug log on stdout.
In order to use it, simply do:
```bash
DEBUG=true bundle exec rspec spec/classes/my_class_spec.rb
```

voxpupuli/modulesync_config,dhoppe/modulesync_config,voxpupuli/modulesync_config,puppet-community/modulesync_config,voxpupuli/modulesync_config,dhoppe/modulesync_config,voxpupuli/modulesync_config,dhoppe/modulesync_config,dhoppe/modulesync_config