Add label to toggle's input for accessibility #186
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When running Web vitals test on a web page using react-toggle, the test complains that there's no accompanying label to the input.
You could surround the Toggle component with a label tag, but it messes up with the styling.
I am talking of cases where you don't need any visible label (before the toggle for instance).
This PR just add a label tag, with the already existing css class "react-toggle-screenreader-only"; before the input element when an id prop is specified. This is done to improve the library accessibility.
Thank you !