Update server instructions for Python 3 (#51)
Update server instructions for Python 3 (#51)

* Update server instructions for Python 3

The simple HTTP server module in Python 3 is 'http.server' not 'SimpleHTTPServer'. See: https://docs.python.org/3/library/http.server.html.

* Update README.md

Clarify Python 2 vs. 3 instructions.

* Update README.md

Remove extra newline.
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