Blender Git Loki

UI: Colors for Texture/Material node sockets and small tweaks

* Set colors for the new texture and material sockets
* Material uses the same color used for shading icons
* Texture uses a plum color desaturated enough to not be confused with Vector's violet
* Image socket adjusted to be closer to Texture sockets but darker
* Integer socket toned down in saturation to not stand out so much
(and be closer to float sockets which are gray)

Making this change now during bcon1 to gather feedback from the community,
and because Geometry Nodes needs to use the new texture/material sockets.