First pass over demos page

I don't know if this PR will do the right thing. I committed some changes to my fork in the demos-page branch and I'm trying to push them to adamantivm's fork.

I took a pass over the demos page to clean up the wording. Some notes on presentation:

The word "hacks" has some positive and some negative connotations. Among the negative connotations are: a quick fix designed to solve a problem in temporary way which will be replaced by a more elegant solution in the future; criminal activity of breaking into secure computer systems and stealing personal information; a fraud who copies work from others. The word "hacker" is more associated with the positive connotations of creatively solving problems, while the word "hack" is generally (in my assessment of popular culture) associated with the negative ones.

Too much promising of "we will do this someday, when we have time" sounds very much like it was written by people who like to talk but don't actually do anything. I deliberately removed most of the "we have grand plans to do X" and focused on what has already been done. If you want that in there, you can revert this PR.