Change the project URL to BitBucket rather than PyPI

Currently, the project metadata on PyPI doesn't provide an easy way to navigate to the BitBucket repo. This change replaces the current self-link back to PyPI with the appropriate link to BitBucket.

--HG--
branch : ncoghlan/setuppy-edited-online-with-bitbucket-1401023748153

setup.py

@@ -121,7 +121,7 @@ setup_params = dict(
     license="PSF or ZPL",
     long_description=long_description,
     keywords="CPAN PyPI distutils eggs package management",
-    url="https://pypi.python.org/pypi/setuptools",
+    url="https://bitbucket.org/pypa/setuptools",
     test_suite='setuptools.tests',
     src_root=src_root,
     packages=setuptools.find_packages(),