Add support for multiple transport instances

Wiston allow to specify differents name for the same transport like this:

```javascript
        new winston.transports.Logio({
            port: 28777,
            name: 'logio.info',
            node_name: 'Dicet',
            host: '127.0.0.1',
            level: 'info',
            localhost: 'info'
        }),
        new winston.transports.Logio({
            port: 28777,
            name: 'logio.verbose',
            node_name: 'Dicet',
            host: '127.0.0.1',
            level: 'verbose',
            localhost: 'verbose'
        }),
        new winston.transports.Logio({
            port: 28777,
            name: 'logio.debug',
            node_name: 'Dicet',
            host: '127.0.0.1',
            level: 'debug',
            localhost: 'debug'
        })
```

Doing this we can create multiple transport instances.