[eslint config] [base] [new] update base ecmaVersion to 2018; remove deprecated experimentalObjectRestSpread option
[eslint config] [base] [new] update base ecmaVersion to 2018; remove deprecated experimentalObjectRestSpread option

bl00mber/javascript,getjll/JavaScript-Style-Guide,airbnb/javascript,ljharb/javascript,cloudability/javascript-style-guide