Change README to Markdown, with some cleaning up for clarity.

Hey Dmitry,

I tried to make the README proper Markdown, and did some rewriting. Overall, I think it's easier to understand and follow the instructions.

I did my best to keep your ideas and original meaning as much as possible. Thanks for what you're doing with RealSync, by the way, it's awesome. We love it at our company.

Let me know what you think of the new README.