refactor CODE

var $loadTweetsButton = $('<button></button>');
        $loadTweetsButton.appendTo($main);
        $loadTweetsButton.click(function() {
          displayHomepage();
        });

        var $newTweet = $('<form id="newTweet"></form>');
        var $visitorName = $('<div><label for="visitorName">Username</label>\n<input type="text" id="visitorName"></div>');
        var $visitorTweet = $('<div><label for="visitorTweet">Tweet</label>\n<input type="text" id="visitorTweet"></div>');
        var $visitorButton = $('<div><input type="submit"></div>');
        var $githubLink = $('<span id="github">Built by <a href="https://github.com/ascherj">Jake Ascher</a></span>');

        $newTweet.append($visitorName, $visitorTweet, $visitorButton);
        $newTweet.appendTo($main);

        $('#newTweet').submit(function(event) {
          event.preventDefault();
          window.visitor = $('#visitorName').val();
          writeTweet($('#visitorTweet').val());
          $('#visitorName').val('');
          $('#visitorTweet').val('');
          displayHomepage();
        });

        var $tweets = $('<div class="tweets"></div>');
        $tweets.appendTo($main);

        function renderTweet(tweet) {
          var $tweet = $('<div></div>');
          $tweet.append('@' + '<a class="user">' + tweet.user + '</a>' + ': ' + tweet.message);
          $tweet.append('<br>');
          var $timestamp = $('<i class="timestamp"></i>');
          $timestamp.append(moment(tweet.created_at).fromNow());
          $timestamp.attr('title', moment(tweet.created_at).format('MMM DD, YYYY, h:mm:ss a'));
          $timestamp.appendTo($tweet);
          $tweet.appendTo($tweets);
        }

        function loadTweets(tweets) {
          $tweets.html('');

          var index = tweets.length - 1;
          while(index >= 0){
            var tweet = tweets[index];
            renderTweet(tweet);
            index -= 1;
          }

          $('.user').on('click', function(event) {
            displayUserTimeline(event.target.text);
          });
        }

        function displayUserTimeline(user) {
          $pageName.text(user + '\'s Timeline');
          $loadTweetsButton.text('Return to Home');
          loadTweets(streams.users[user]);
        }

        function displayHomepage() {
          $pageName.text('Homepage');
          $loadTweetsButton.text('Load New Tweets');
          loadTweets(streams.home);
        }

        displayHomepage();
        $main.append($githubLink);