Updating the homepage

[Yavor Doganov]

Would Emacs developers object if I convert the current homepage to the
new template [1]?  This kind of activity is listed in the server task
list [2].  I will certainly keep the same text, later on someone
inside the project can update the inaccurate information.

I think it is a good thing to do in the eve of the forthcoming
release.  When Emacs 22 is out, thousands of people will visit
gnu.org/s/emacs and the new layout contains many important links.  If
0.1% of these people read about our philosophy or donate to the FSF,
that would be a big plus.

[If required, I can send here full diff (context or unified?) of the
changes, before I commit them.]

[1] http://gnu.org/boilerplate.html
[2] http://gnu.org/server/tasks.html