function isURL(url) {
    /*
    Test the string against the URL pattern and return if it matches
    */
    var pattern = /(ftp|http|https):\/\/(\w+:{0,1}\w*@)?(\S+)(:[0-9]+)?(\/|\/([\w#!:.?+=&%@!\-\/]))?/;

    return pattern.test(url);
  }
Determines if the string passed in is a URL or not

Public Accessor: AmplitudeHelpers.isURL( url )

@access public
@param {string} url - The string we are testing to see if it's a URL.
@returns {boolean} True if the string is a url, false if it is not.