title: How to log "catched" exceptions?
body: <p>When <a href="https://github.com/flatiron/winston">winston</a> handles uncaught exceptions it prints a nice info of the uncaught exception.How can I do the same on "catched exceptions"?</p>
  
  <pre><code>if (err) {
   // winston. log the catched exception
  }
  </code></pre>
  
  <p>I checked the source and there seems to be a <a href="https://github.com/flatiron/winston/blob/master/lib/winston/transports/transport.js#L105-L121"><code>logException</code> method</a> but I don't know how I could use it.</p>
  
  <pre><code>var logger = new winston.Logger({
    transports: [new winston.transports.Console({handleExceptions: true})]
  })
  var err = new Error('test error.')
  logger.logException(err.message) //no method 'logException'
  </code></pre>