Feature request: Allow colors based on score brackets in addition to existing gradient

[glennbarrett]

Currently score-based coloring is forced to use an automatic gradient within the score range. Would it be possible to add set colors for specific score ranges as an additional option? Possibly a toggle between the two modes?

This would allow greater control over colors for some use cases, and also help a lot with layer-math based combines between already scored layers.

For example:
Score range 0-0: Color1
Score range 1-5: Color2
Score range 6-10: Color3
Score range 11+ : Color4