Will crash if sec-websocket-protocol has only one value

[zexee]

WebSocket-for-Python/ws4py/client/__init__.py

Line 336 in cdf50bd

protocols = ','.join(value)

I don't know much about websocket but when use this to connect libwebsocket-based server, it will crash, and the error comes from this line. The value is b'ws'. Simply change this line to protocols = value, and it works fine.