This patch changes how the color ramps are drawn by adding handles for the colour elements and also displaying a guide ramp without alpha.
The handles make it easier to see the elements and they also show the colour.
The guide ramp shows the gradient without alpha. This makes it much easier to visualise the alpha content of a ramp.
Note: Selection code has not changed so it still uses the same logic so clicking in the middle of the ramp will still select the handle.