v2.0.0 Removed option to pass initial value

• Breaking: you can no longer pass an initial state object to useQueryString.
• The module now also exports queryStringContext

The initialValue option was removed, because it was inconsistent in behaviour when using it with or without a server side QueryStringProvider. To use default values, you can use the following patterns:

const [{ search = '' }, setQueryString] = useQueryString()

const [{ search = '' }, setQueryString] = useQueryString()
const [input, setInput] = React.useState(search)

Or (when you don't have a server side QueryStringProvider:

const [{ search = '' }, setQueryString] = useQueryString()
const [input, setInput] = React.useState('')

React.useEffect(
  () => { setInput(search) },
  [search]
)