Updated installation instructions, expanding on new techniques available to Windows 8 users and clarifying which technique Mac OS X users should use. Fixes #59.

Use zip files rather than tar files for source distributions of setuptools itself. Fixes #7 for users of Python 2.7.4 and later.

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extra : source : 81bfac3cf9a11fbb52b43cb3106419085ac8aee5
extra : histedit_source : 942f45916acfe482998d0cb7adefc08f095dcf0c

branching to 0.7 now, as I wanted this wart gone before anything went
into Python 2.5.  But it's gone now, yay!

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extra : source : f3c5c19842064dd4a497baef0171aac54464a484
extra : amend_source : 3f79e71eedfc5f37a1813967bb53cf9d92a11919

The overridden version cannot handle Python 3.x while distutils verion can
handle it just fine.

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extra : rebase_source : 86fa56285849e97780e91eff405881bfb72184d5

Setuptools now honors all dependency_links and not just the first one that was supplied.

(builtins.open() is io.open() in Python 3.)

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extra : amend_source : 46787fd35452f54da1a8afd2bf8a30dff920d8a2