Fix/support for short color notation

[bdlabs]

Fixed render svg. Add support for short color notation.

[skanaar]

Very interesting to let uers register their own styles!
I will have to think a bit about this as this new public API will freeze the current implementation of layouters and visualizers.

[bdlabs]

OK, can you explain how? Maybe I missed something :)

[skanaar]

@bdlabs the sames changes appear in both this PR and in #193 . I got a bit confused.

What I mean is that right now the layouter and visualizer systems are private parts of nomnoml. So I am free to change them around whenever without breaking the public API.

If they are exposed they are "locked into place" and any changes to those systems would mean a breaking change.
So I would have to think carefully about that.

[skanaar]

Could you remove the stuff related to registerComponent from this PR so it only deals with the color notation? Thanks

[bdlabs]

My mistake, I did the merge wrong, didn't notice it :), I'll fix it today. Thanks.

[bdlabs]

Hi, what about this theme? :)

[skanaar]

Thank you for the reminder. I'm on a short vacation for the moment, will look at this next week.

[skanaar]

@bdlabs which SVG viewer are you using that gave you a buggy rendering?
Because I cannot reproduce the bug that this is supposed to solve.

[bdlabs]

@skanaar sorry, I don't remember. It was probably a render in phpstorm.

[skanaar]

Hmm, I will close this PR since I cannot reproduce the bug.
But I really appreciate the effort.

[skanaar]

Reopening as I can reproduce it in JetBrains Fleet.