Rename option

[stevenvachon]

It'd be nice if we could do this:

const args = commandLineArgs([
    { name: 'opt-name', type: Boolean, rename: 'optName' }
]);

console.log(args);
//-> { optName: true }

It would help make our code cleaner, by not needing args['opt-name'] nor custom code to replace properties.

[75lb]

duplicate of #57