title: jVectorMap: Update Scale
body: <p>I'm having a hard time updating the scale of the region in a map created with jVectorMap (whereas updating values with new data works just fine):</p>
  
  <pre><code>{"data":{"title":"A or B?","values":{"DE":"A","AT":"A","CH":"B"},"scale":{"A":"#FFCC00","B":"#00AEB5"}}}
  
  worldmap.series.regions[0].setValues(dataCountry.data.values); //ok, values are being updated
  worldmap.series.regions[0].setScale(dataCountry.data.scale); //TypeError: this.scale.setScale is not a function
  </code></pre>
  
  <p>Any hint is highly appreciated!</p>