Highlight "nil" with the same color as the one used for other builtin types

[dlsniper]

Should we highlight nil with the same color as the other built in types?
According to go's builtin.go file, nil is a var and we highlight it as such, but sometimes, reading the code, it's not that clear (my mind always try to see it as a builtin / color even).

I guess, an even better question would be if we should highlight the builtin types with a different color altogether.

I can work on this as I'm familiar with that part of the code but I want to have some input before doing so. What are other people thinking about this?

[zolotov]

I don't mind to introduce yet another text attribute settings for builtin variables/constants (nil, true, false). Not as default of course.

[bingamic]

Just found this issue as I wondered why true/false was not highlighted.
If your looking for user feedback, than I think it does provide value for readability.

[zolotov]

@bingamic sure, we always appreciate user feedback. Thank you for the opinion.

[dlsniper]

Btw, this should be simple to fix but I'm waiting for #2293 to be merged first.