Get rid of relative imports in all unittests.  Now anything that
imports e.g. test_support must do so using an absolute package name
such as "import test.test_support" or "from test import test_support".

This also updates the README in Lib/test, and gets rid of the
duplicate data dirctory in Lib/test/data (replaced by
Lib/email/test/data).

Now Tim and Jack can have at it. :)
diff --git a/Lib/test/test_threadedtempfile.py b/Lib/test/test_threadedtempfile.py
index 9aa9376..2b5ecf2 100644
--- a/Lib/test/test_threadedtempfile.py
+++ b/Lib/test/test_threadedtempfile.py
@@ -22,7 +22,7 @@
 
 import thread # If this fails, we can't test this module
 import threading
-from test_support import TestFailed
+from test.test_support import TestFailed
 import StringIO
 from traceback import print_exc