title: How to change the font size of title property of a hubtile
body: <p>i am using the hubtile control from the Microsoft.Phone.Controls.Toolkit
  the xaml code for it is</p>
  
  <pre><code>&lt;toolkit:HubTile x:Name="hub" Margin="12,12,0,0"                                             
                           Title="{Binding Title}"                        
                           Message="{Binding Message}"
                           Source="{Binding Image}"
                           GroupTag="BindingHubTile" Tap="HubTile_Tap_1"&gt;
                                  &lt;/toolkit:HubTile&gt;
  </code></pre>
  
  <p>how to change the font size of the title property so that the whole title fits in?</p>