Adds an item with the cpesified color and value to the palette.
If an item with the same value already exists in the palette,
it is replaced by the new one. Note that internally the component sorts the
palette in ascending order so that you don't have to worry about the sequence
in which you insert items.
Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2