Support eslint quote-props rule

[danvk]

I'd like a rule equivalent to eslint's quote-props, so that I can enforce that object keys are quoted only when necessary.

i.e. I'd like a setting to make this illegal:

const o = { 'name': 123 };

in favor of:

const o = { name: 123 };

[adidahiya]

sounds like a good rule to me. open to PRs.