Support sending "array" types for binary data

Migrated from https://github.com/google/pywebsocket/issues/131:
```
What steps will reproduce the problem?
1. Construct an array using array.array()
2. Attempt to send it using request.ws_stream.send_message(message, binary=True)

Expected result:

Binary data is sent.

Actual result:

TypeError: web_socket_transfer_data raised exception for /flow-control-test:
cannot concatenate 'str' and 'array.array' objects

Probably a TypeError would be appropriate if binary=False, but when binary=True
this seems a natural way to send large binary objects.
```
Original issue reported on code.google.com by ri...@google.com on 10 Jul 2014 at 10:18