code: function containsWords(wordlist, str) {
      var i;
      var matches = [];
      for (i = 0; i < wordlist.length; i++) {
          var re = new RegExp("\\b" + wordlist[i] + "\\b", "i");
          if (re.exec(str)) {
              matches.push(wordlist[i]);
          }
      }
      return matches;
  }
docs: Determines if any of the words in wordlist appear in str.
  
  @param {String[]} wordlist list of words to check
  @param {String} str to check for words
  @return {String[]} words that matched