treewide: add accentColor Option

[lwb-2021]

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[trueNAHO]

Combining the base16 scheme with an arbitrary subset of a semantic representation introduces subtle breaking changes, further ambiguates the style guide, and undesirably encourages bloating the base16 scheme with unrelated features. I am against this.

Full semantic support is pending in #892 and I will take care of this once I get to it.

[lwb-2021]

How will it support accent color instead of just using blue as accent color or just replacing blue with accent color?

[trueNAHO]

How will it support accent color instead of just using blue as accent color or just replacing blue with accent color?

Could you be more specific? I do not understand.

Why do you only want accent colors?

[lwb-2021]

How will it support accent color instead of just using blue as accent color or just replacing blue with accent color?

Could you be more specific? I do not understand.

Why do you only want accent colors?

Now we use base0D as blue and accent color, and if we want to change accent color by changing base0D(for example to mavue) we may get mavue where we expect to get blue(for example, in nixos-icons).