Add SourceForge download support, graciously contributed by Ian Bicking. Also, move some more imports to the top.
Add SourceForge download support, graciously contributed by Ian Bicking.
Also, move some more imports to the top.

--HG--
branch : setuptools
extra : convert_revision : svn%3A6015fed2-1504-0410-9fe1-9d1591cc4771/sandbox/trunk/setuptools%4041027

pypa/setuptools,pypa/setuptools,pypa/setuptools