Re-use texture input nodes

[tdapper]

Quoting myself from #32:

One possible optimization (not sure if it has any performance implications, but it may simplify/clarify the material graph): Perhaps keep a list of texture input nodes around and just re-use a node when a texture is used multiple times (with the same color space setting). In the example above, e.g. the input node for the front BSDF color could be re-used as input to the Mix BSDF node.

[dvhart]

Due to changes in the Laubwerk API and the lack of current API documentation, I am no longer able to develop or maintain Thicket. Consider trying Laubwerk’s fork of thicket:

https://github.com/Laubwerk/player-for-blender

Thank you for using Thicket, it was a lot of fun to develop.