[Pydotorg-redesign] Tweaking the top page

[A.M. Kuchling]

Here's a revision of the top page of python.org:
http://www.amk.ca/python.org.html .  Comparing it with the current
contents of www.python.org will be helpful.  My goal is to get it all
on-screen at once, but that goal is still distant. Changes:

* The sidebar links have been rearranged.  The existing headings of
  "Special Topics", "Popular Links", "Exits", "Commercial Exits",
  "Python Help" are rather vague.  My revision reorganizes the links
  under "Python versions", "Documentation", and "Development" and drops
  redundant links.  The sidebar is still too darned long, though; can we 
  drop some of the Exits and most of the Commercial Exits.

* The eight links in the top bar aren't repeated in the body any more.

Other changes I'd like to make: 

* Drop the OSI logo; show it on the "About Python" page.

* Shrink the big logo.

Other suggestions for changes?

--amk