Method RenderCell
RenderCell(Attribute, string, bool)
Override to provide custom multi colouring to cells. Use Driver to
with AddStr(ustring). The driver will already be
in the correct place when rendering and you must render the full render
or the view will not look right. For simpler provision of color use ColorGetter
For changing the content that is rendered use RepresentationGetter
protected virtual void RenderCell(Attribute cellColor, string render, bool isPrimaryCell)