clean out the installClose action as we no longer use that

index.js

@@ -62,10 +62,6 @@ require.def(['require', 'jquery', 'hashDispatch'],
         }
 
         $('body')
-            .delegate('#installClose', 'click', function (evt) {
-                //Allow closing the installed area thing.
-                $('#installed').fadeOut(500);
-            })
             .delegate('#firefox', 'click', function (evt) {
                 location = 'http://getfirefox.com';
             });

style.css

@@ -105,23 +105,6 @@ strong {
   margin: -1px 4px 0 0;
 }
 
-#installClose {
-  text-align: center;
-  font-size: 12px;
-  z-index: 101;
-}
-
-a#installClose {
-  cursor: pointer;
-  color: #ff5959;
-  float: right;
-}
-
-a#installClose:hover {
-  text-decoration: none;
-  color: red;
-}
-
 #shareArrow {
   position: fixed;
   top: 0;