Enable Color Pickers with Defined HSV Subspace. ( New Feature Request )

@SirFizX, this seems reasonable to me, but I would like to hear what @sebavan thinks since there is another thread talking about HSV in the node material editor and there have been suggestions to go with a different color space that works similarly to HSV but does not have some of the branching logic when converting between spaces which are a killer in shaders. It would make sense if we adopt a new color space in one part of the engine that we use that same space everywhere.