lowercase-keys 
Lowercase the keys of an object
Install
$ npm install lowercase-keys
Usage
const lowercaseKeys = require('lowercase-keys');
lowercaseKeys({FOO: true, bAr: false});
//=> {foo: true, bar: false}
API
lowercaseKeys(object)
Returns a new object with the keys lowercased.
License
MIT © Sindre Sorhus