Support more decimal places for higher precision

[jhogue]

I have noticed that when I move a color around and then go back to the original values, the color is not exactly the same as the original. Its off very slightly. I think this is due to decimal rounding.

Now, in the input steppers, moving by a tenth would be annoying, but, maybe this is worth investigating to see what the user experience is like. Support one more decimal place on HSL and see how it works. If its more trouble to play with and customize because of the extra decimal place, we drop it and close this issue.