Move leap to lib/compiler/samples.

samples/leap/leap.css

Index: samples/leap/leap.css
===================================================================
--- samples/leap/leap.css	(revision 13412)
+++ samples/leap/leap.css	(working copy)
@@ -1,34 +0,0 @@
-/* Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
- * for details. All rights reserved. Use of this source code is governed by a
- * BSD-style license that can be found in the LICENSE file.
- */
-
-#popup {
-  position: fixed;
-  width: 400px;
-  background: yellow;
-  border: thin solid red;
-  z-index: 100;
-  top: 0px;
-  left: 0px;
-  visibility: hidden;
-  white-space: pre-wrap
-}
-
-#outline {
-  position: fixed;
-  width: 250px;
-  border: solid;
-  padding: 5px;
-}
-
-#editor {
-  position: absolute;
-  left: 280px;
-  border: solid;
-  padding: 5px;
-}
-
-#code {
-  white-space: pre;
-}