move node colors to central file

[GamerXD8991]

I'm not sure what's your vision with Traduction vs Translation but for now I used it to implement colors

[Half-and-Xat]

Hmm, I thought more in the direction of structuring the color as categories. So nodes and wires do not have color entries in the color file, but rather connect to a predefined category (that we can extent if required). This way we only need to apply a category to any new node and it automatically will get the correct color. It is also easier to expose colors to settings on a later PR and it is especially easier to maintain.

I also think the file shouldn't be named "node_color", since we should also bind other things to it as data types (wire colors).

If you ask me, you can use the context menu categories for now. It is still something we have to refine at some point, but for now it should already be an improvement.

But please wait for @Lluciocc before you do the job three times. I am not familiar with Python and don't know what methods/functions are the best.