Websocket: first commit

[rd4com]

Hello, here is what we've got so far:

• upgrade http request to websocket
• send all size
• receive all size
• works with select for non-blocking

all sizes means len(data) <=125, <2**16, <((2**64)>>8)

 

Many things not done:

• ping/pong
• fragment message

(and more)

 

There is a need to think about how it's gonna be integrated, we'll need to organize the flags in aliases, for example.

Error handling seem like a great priority :+1:

 

Note that the code appears to be more complicated than what it is doing, because we're doing extra steps to work with ByteArray (PythonObject) in this example.