Light Color Manipulator

"This is in response to a wishlist item that the wirecolor of lights should reflect the light's actual color. This isn't quite that. but does show the color and multiplier of selected lights in the viewport when manipulate mode is on. It's not exactly a manipulator as you can't change anything with it. but it's written as one.
based on the Generic Radius Manipulator code by Scott Morrison and light_manipulators.ms by Borislav Petrov"