added the CFP form to the front page, corrected some typos, moved the de...

...adlines section up a bit, and made some formatting changes to improve readability and consistency.

We might consider moving the CFP form to a subpage if we redesign it or when we have more content, but in an effort to keep things simple, I embedded it into the home page for now. I reorganized a few things so that the CFP form would be near the bottom (just above Twitter) to avoid pushing things like the deadlines too far down.