[ZWeb] Zope Book setup

[Jeffrey P Shell]

As an FYI: I've done a couple of things over the weekend and this 
morning concerning the Zope Book.

First - I made the 2.6 edition current.  My memory is telling me that 
someone requested this (I believe it was Chris McDonough, but I haven't 
found evidence to support my claim since).  I initially did this by 
renaming the 2.6 edition to 'current' since a lot of old links were 
based on that.  But apparently there are links into the 2.6 edition 
explicitly.

So I've added a redirector through the ZMI in that folder called 
'current' that redirects to the 2.6 edition.  If a 2.7 edition gets 
done in time for the release of Zope 2.9, we can update the 'current' 
redirector to point to that.

I'd like to keep the old editions around.  I've found that this has 
been helpful with Python (being able to go back to module documentation 
for 2.1 or 1.5).  It may not apply as much to the Zope Book, since it's 
a different beast than Python.  But I imagine it would be helpful to 
those running old versions of Zope for maintenance reasons that need to 
refer back.

Jeffrey P Shell, jeffrey at cuemedia.com