title: In the Vuetify data table, table column with slot template
body: <p>In the Vuetify data table,  for table column with slot template is it possible to use column name with Camel casing, currently supporting only column names, with lower case in the model for example</p>
  
  <p>This does not work:</p>
  
  <pre><code>   &lt;template v-slot:item.firstName="{item}"&gt;
         &lt;span&gt;{{item.prefix}} {{item.firstName}} {{item.lastName}} &lt;/span&gt;
     &lt;/template&gt;
  </code></pre>
  
  <p>This works :</p>
  
  <pre><code>   &lt;template v-slot:item.firstname="{item}"&gt;
         &lt;span&gt;{{item.prefix}} {{item.firstname}} {{item.lastname}} &lt;/span&gt;
     &lt;/template&gt;
  </code></pre>
  
  <p>My data model is having properties like this.</p>
  
  <pre><code>contactsList: {
    {lastName : "Ray",
    firstName : "Sam",
     prefix : "Dr."},
    {lastName : "Bank",
     firstName : "Paul",
     prefix : "Jr."}}
  </code></pre>