fix to.keyword returning Object.prototype values

[matias-la]

$ node
Welcome to Node.js v16.9.1.
Type ".help" for more information.
> require('color-string').to.keyword(['constructor'])
[Function: Object]

The package had unexpected behavior when passing properties of Object.prototype to to.keyword. Using a null prototype for reverseNames fixes the issue.

[Qix-]

Mrh I was hoping we could just replace it with a Map but this package hasn't been updated to even es6 syntax yet so surely that would break something.

Thanks for the PR, LGTM.

[matias-la]

Thanks for responding so fast :) Would it be possible to make a release including this change?

[Qix-]

Yeah sorry was making sure the builds were green then got sidetracked. Releasing now.

[Qix-]

Released as 1.9.1, thanks again :)

[matias-la]

Mrh I was hoping we could just replace it with a Map but this package hasn't been updated to even es6 syntax yet so surely that would break something.

I might send similar PRs for the color package. I'll use null prototypes and/or hasOwnProperty checks unless you prefer me to use Map instead.

[matias-la]

Actually, it seems we won't need to use the color package anymore as we will develop an in-house alternative. Thanks anyway for the fast release!