pessimistically hold off on transmitting a request body until a server gives the go-ahead.
 *  New: Permit network interceptors to rewrite the host header for HTTP/2. This makes it possible
    to do domain fronting.
 *  New: charset support for `Credentials.basic()`.


## Version 3.5.0

_2016-11-30_

 *  **Web Sockets are now a stable feature of OkHttp.** Since being introduced as a beta feature in