[plt-dev] Racket web page

A few of us (Robby, Jay, Matthias, Eli, and I) have been working on the
Racket web page. Here's what we've come up with, so far:

  http://www.cs.utah.edu/~mflatt/tmp/r/www/

Besides a different look, the main goal is to explain better what
Racket is and why Racket is different.

We'd like to have more 7-line programs for the middle slideshow, so
please contribute.

Otherwise, let's have feedback on the content first, please. Then we
can discuss which shade of black to use for title bar. :)