Blend Images - Overview of Missing or Extra blend Modes that exist between Photoshop and chaiNNer

[mrjschulte]

When #2664 is merged, here are the remaining blend mode differences between Adobe Photoshop and chaiNNer:

Here are the missing blend modes that PS has and that chaiNNer doesn't have: darker color, lighter color, hard mix, Hue, Saturation, Color, Luminosity.

These are the Extra blend modes that chaiNNer has and PS doesn't: reflect, glow, negation, Xor

Leaving this issue here as a memo for @mrjschulte to look into adding support for the remaining "pure math" layer transfer modes such as darker color, lighter color and hard mix.