Renamed copy_reg to copyreg in the standard library, to avoid
spurious warnings and ease later merging to py3k branch. Public
documentation remains intact.
guarantee to keep valid pointers in its slots.
tests: Moved ExtensionSaver from test_copy_reg into pickletester, and
use it both places. Once extension codes get assigned, it won't be
safe to overwrite them willy nilly in test suites, and ExtensionSaver
does a thorough job of undoing any possible damage.
Beefed up the EXT[124] tests a bit, to check the smallest and largest
codes in each opcode's range too.
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. :)