function unescape(string) {
      return string == null ? '' : String(string).replace(reEscapedHtml, unescapeHtmlChar);
    }
The inverse of `_.escape` this method converts the HTML entities
`&amp;`, `&lt;`, `&gt;`, `&quot;`, and `&#39;` in `string` to their
corresponding characters.

@static
@memberOf _
@category Utilities
@param {string} string The string to unescape.
@returns {string} Returns the unescaped string.
@example

_.unescape('Fred, Barney &amp; Pebbles');
// => 'Fred, Barney & Pebbles'