title: Change the font of a column header in DevExpress grid
body: <p>I have a DevExpress grid that has some editable columns.
  Would like the user to know easily they are editable so thought about changing the column header to 'Bold'.</p>
  
  <pre><code>&lt;dxg:GridControl.Columns&gt;
      &lt;dxg:GridColumn Header="Region" FieldName="Region" ReadOnly="False" Style="{StaticResource DxEditableColumnsStyle}" /&gt;
      &lt;dxg:GridColumn Header="Id" FieldName="Id" ReadOnly="True" Style="{StaticResource DxColumnsStyle}"/&gt;
      &lt;dxg:GridColumn Header="Entity" FieldName="Entity" ReadOnly="False" Style="{StaticResource DxEditableColumnsStyle}"/&gt;
  &lt;/dxg:GridControl.Columns&gt;
  </code></pre>
  
  <p>Woudl you know how to do so? I've tried updating this through some setters in my dictonnary but it doesn't work:</p>
  
  <pre><code>&lt;Style TargetType="dxg:GridColumn" x:Key="DxEditableColumnsStyle"&gt;
      &lt;Setter Property="CellStyle"&gt;
          &lt;Setter.Value&gt;
              &lt;Style TargetType="{x:Type dxg:GridColumn}"&gt;
                  &lt;Setter Property="TextBlock.FontWeight" Value="Bold" /&gt;
              &lt;/Style&gt;
          &lt;/Setter.Value&gt;
      &lt;/Setter&gt;
  &lt;/Style&gt;
  </code></pre>
  
  <p>thank you!</p>