Import ruby-websocket-extensions-0.1.2 as www/ruby-websocket-extensions.

A minimal framework that supports the implementation of WebSocket
extensions in a way that's decoupled from the main protocol.
This library aims to allow a WebSocket extension to be written and
used with any protocol library, by defining abstract representations
of frames and messages that allow modules to co-operate.

websocket-extensions provides a container for registering extension
plugins, and provides all the functions required to negotiate which
extensions to use during a session via the Sec-WebSocket-Extensions
header.

(tsutsui)