Switch pkg packages, pub, and dartdoc to use package: imports.

This also changes the SDK layout by replacing the "pkg" directory, which
contained the full source of all the packages needed by pub and dartdoc, with a
"packages" directory that contains only their lib directories. This directory is
used as the package root for pub and dartdoc when run from the SDK.

BUG=6745

Review URL: https://codereview.chromium.org//12782016

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart/pkg/logging@20640 260f80e4-7a28-3924-810f-c04153c831b5
diff --git a/test/logging_test.dart b/test/logging_test.dart
index 5102c42..1af342f 100644
--- a/test/logging_test.dart
+++ b/test/logging_test.dart
@@ -5,7 +5,7 @@
 
 library logging_test;
 
-import '../../../pkg/logging/lib/logging.dart';
+import 'package:logging/logging.dart';
 import 'package:unittest/unittest.dart';
 
 main() {