I'm trying to create something a little like a quantize scale, but act like a linear color scale?

When I try to put multiple colors into a linear scale, it seems to only scale between the first two colors.

I'd like multiple colors like a quantize scale, but fade between those colors. I'm unsure if this is possible.

```
//red and green works ok
var color = d3.scale.linear()
            .range(['red','green']);

//doesn't work - only red and green show
var color = d3.scale.linear()
            .range(['red','green', 'blue']);

//red green and blue show, however it doesn't fade between the colors
var color = d3.scale.quantize()
            .range(['red','green', 'blue']);

```