This change also adds a minimal unittest of urllib.response.addbase.
More are needed, but not to cover the small change being made here.
Addresses http://bugs.python.org/issue5418
It consists of code from urllib, urllib2, urlparse, and robotparser.
The old modules have all been removed. The new package has five
submodules: urllib.parse, urllib.request, urllib.response,
urllib.error, and urllib.robotparser. The urllib.request.urlopen()
function uses the url opener from urllib2.
Note that the unittests have not been renamed for the
beta, but they will be renamed in the future.
Joint work with Senthil Kumaran.
Raymond Hettinger
Jeremy Hylton
Antoine Pitrou