Function: fill_image

DOC_MSE_VERSION: since 2.6.0

--Usage--
> fill_image(input: image, color: color)

Fill an image with a single color, but keep the alpha channel unchanged.


--Parameters--
! Parameter	Type			Description
| @input@	[[type:image]]		Image to fill.
| @color@	[[type:color]]		Color to fill with.
