Added a util to check toggle status.

What's changed?

You can now import isON that returns true when the toggle status is "on" or false otherwise.

Usage

import { LaunchLever, isOn } from "launch-lever"

const toggles = new LaunchLever(your-toggle-list).flags
const pfx-123 = isOn(toggles.pfx-123) 

Initial release

Initial release