/**
 * Converts ampersands, angle brackets, apostrophes and blockquotes to their HTML encoded equivalents
 *
 * @function
 * @name escapeHtml
 * @param {string} val A string values to escape
 * @returns {string} The original value (converted to string) and with any of the unallowed characters properly escaped (null/undefined values are converted to '')
 */
export default function escapeHtml(val: string): string