VerticalHeaders
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Shows how to use a CellFactory to render column headers in the vertical direction.

Rendering column headers using vertical text can be advantageous for columns with
wide headers and narrow data (e.g. integers or Booleans).

This may seem like a simple task at first, just create the content as usual and
apply a RotateTransform. However, this approach will not work. Unlike WPF, which
has LayoutTransform and RenderTransform properties, Silverlight only has 
RenderTransform, which is applied only after the layout pass has been applied.
If you rotate a Silverlight element, the element's Width and Height values are 
swapped, but only after the content has already been laid out and possibly clipped
to the original dimensions.

The solution is to use a C1LayoutTransformer element available in the C1.Silverlight
assembly. This element provides a LayoutTransform property that works like the native
LayoutTransform in WPF (or the LayoutTransformer element in the Silverlight SDK).

For a detailed discussion of layout versus render transforms, please refer to

	http://blogs.msdn.com/b/silverlight_sdk/archive/2009/12/16/using-the-silverlight-toolkit-layouttransformer-control.aspx

