`FormEncodingBuilder` with the more powerful `FormBody` and
    `FormBody.Builder` combo. Similarly we've upgraded `MultipartBuilder` into
    `MultipartBody`, `MultipartBody.Part`, and `MultipartBody.Builder`.

 *  **The Apache HTTP client and HttpURLConnection APIs are deprecated.** They
    continue to work as they always have, but we're moving everything to the new

    above. See [Jetty's overview][jetty_8_252] of the API change and its consequences.

 *  New: `MultipartReader` is a streaming decoder for [MIME multipart (RFC 2045)][rfc_2045]
    messages. It complements `MultipartBody` which is our streaming encoder.

    ```kotlin
    val response: Response = call.execute()
    val multipartReader = MultipartReader(response.body!!)

    multipartReader.use {
      while (true) {

 *  New: `OkHttpClient.webSocketCloseTimeout` configures how long a web socket connection will wait
    for a graceful shutdown before it performs an abrupt shutdown.

 *  Fix: Honor `RequestBody.isOneShot()` in `MultipartBody`

 *  Fix in `okhttp-coroutines`: Don't leak response bodies in `executeAsync()`. We had a bug where
    we didn't call `Response.close()` if the coroutine was canceled before its response was
    returned.