make fromHSL public, add toHSL

[Matthew Woehlke]

Olaf Schmidt wrote:
> I am not sure whether the HSL colour space which Matthew suggests to make 
> public is actually identical to my sHSL colourspace for colour manipulations 
> and contrast evaluations, but if it is, then I see no need to have several 
> implementations of it in parallel.

It isn't. IMO your color space is correctly termed H'C'Y' :-), but at 
any rate it different from the HSL needed for khtml W3C standards and as 
used in Windows.

-- 
Matthew
So, an astrophysicist, a quantum physicist, and an astrologer walk into 
a bar...