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. :)
declarations and weird markup that we used to accept & ignore that recent
versions raised an exception for; the original behavior has been restored
and augmented (the user can decide what to do if they care; the default is
to ignore it as done in early versions).