Cleanup README.md

I moved the contents of README into README.md, markdownified it (well now it's a word), added a short description of the project and the abstract from the paper. This should look much better on GitHub. ([This](https://github.com/infogulch/Comparison-Programming-Languages-Economics/blob/ae238b63e8ed0076203adaf9f4c0b9de188bc0b5/README.md) is what it will look like on the project home page.)

I am unsure if this is the description text you'd like to use. Let me know what you'd rather it be and I'll update the pull request.