Added text blob from the page source of
http://www.pythonchallenge.com/pc/def/equality.html
Implemented two helper functions findMiddle() and stripUpper().
The output is quite sparse, however, with lots of blank list elements,
so we are currently debugging our code to make the output prettier.
We are returning all the lower-case letters resulting from
findMiddle() and stripUpper() and concatenating all strings in sublists
into one long string.

We tried to plug this in as the URL for level 4, but it doesn't seem
to work.

Do we now need to apply a Caesar shift to the letters?