Added encoding line to server.py

Some versions of Python may complain about the little UTF-8 '©' in the file.

```
SyntaxError: Non-ASCII character '\xc2' in file server.py on line 19
```

I added the [`coding`](http://www.python.org/dev/peps/pep-0263/) thing on line 2 to fix it.

BY THE WAY, how does licensing work with pull requests?